Research Topics

PhD research topics available for the research phase of the program

If you apply directly for the research phase since you already obtain a qualifying master's degree, you will have to state your preferences for at least one and a maximum of three of our research fields. The Fellows working in the respective research area(s) will then see your application and you might already meet them in the application interviews.

On this page, you find a list of all our research fields. With a click on each field, you find sample Ph.D. topics of the individual Fellows that are currently available. Please note, that the topics might change until you start your research phase at the MPSP or the Fellows might also provide you with individual suitable topics. Nevertheless, the listed Ph.D. topics should serve as initial inspiration and decision-making aid for your preferred research fields.

If you want to learn more about the individual Fellows, you can check them out here


Prof. Henry Chapman (Hamburg)
  • Lensless Imaging using Coherent Electrons
  • The methods of coherent diffractive imaging and ptychography replace a lens with an algorithm to obtain quantitative phase-sensitive images, and may provide advantages over conventional electron microscopy of macromolecules. This project will develop simulations of coherent electron diffraction under realistic conditions and compare with experiments, and investigate new algorithms to recover images from the diffraction data. We are looking for a candidate with a strong interest in imaging and Fourier optics, and who is capable of programming and performing data visualisation.

  • High resolution X-ray holography
  • One aspect of in-line holography is that the reference wave greatly amplifies the weak scattered wave from a small object such as a virus. With revolutionary new X-ray optics it becomes possible to record highly magnified in-line holograms of nanometer-sized objects. This project will explore the potentials of this for imaging biological materials, investigate the dose requirements, and experimentally demonstrate 3D imaging. The successful candidate should have a strong background in optics and imaging, and strong programming skills.

  • Time-resolved serial crystallography
  • This project will extend the method of serial femtosecond crystallography using X-ray free-electron lasers and synchrotron radiation facilities to investigate the dynamics of proteins induced by novel triggers, such as terahertz radiation or photo-acoustic waves. The candidate will have a unique opportunity to work on forefront research at advanced X-ray facilities as well as develop and test new experimental methods in the laboratory. The project combines experimental physics, structural biology, and computational analysis. We are therefore searching for a candidate with a strong interest in multidisciplinary research.


    Dr. Maria Chekhova (Erlangen-Nürnberg)
  • Third-order parametric down-conversion
  • The goal is to experimentally observe a new nonlinear optical effect: direct decay of a photon in three, the inverse to the third harmonic generation. This effect, called third-order parametric down-conversion, is an upgrade of spontaneous parametric down-conversion (SPDC). It is far more unusual and interesting than SPDC: it results in quantum states of light with negative Wigner functions and it offers a realization of a cubic quantum gate, highly demanded in quantum information. Despite many theoretical works and several experimental attempts with nonlinear crystals, waveguides, and fibers, it has been not observed so far. In this PhD project the concept is to use a new class of materials, namely ultrathin layers with giant cubic nonlinearities (semiconductors, chalcogenide glass, metasurfaces) where phase matching will be not needed.

  • Loss-tolerant quantum imaging with twin beams
  • One of the ways to enhance signal-to-noise ratio in imaging is to illuminate an object with twin beams, for which the photon numbers are correlated. Such twin beams are produced at the output of a nonlinear crystal through high-gain parametric down-conversion. However, this technique is useless if the detection efficiency is not extremely high. The project aims at further developing this technique by adding phase sensitive parametric amplification of the image, which will make the imaging tolerant to any loss and therefore suitable for ‘difficult’ spectral ranges like IR and terahertz.


    Prof. Stefan Hell (Göttingen)
  • Far-Field Optical Imaging at Molecular Resolution
  • New concepts have radically overcome the longstanding limits to optical analysis of molecular systems. Optical resolutions of a few nano¬meters have been demonstrated, well beyond Abbe’s diffraction limit, for example with the recent MINFLUX concept (Science 355, 606-612 (2017)). This opens up entirely new experimental opportunities, breaking new ground in the study of macromolecules and beyond. The successful candidate will develop advanced optical instrumentation and investigate physical imaging conditions and resolution performance. Alternatively, a related project involving theoretical optical analysis and modelling can be offered. The candidate should have (or expect to complete soon) a Master’s or equivalent degree in Physics or Physical Chemistry or a comparable qualification.


    Prof. Ulrich Nienhaus (Karlsruhe)
  • Advanced Flourescence Microscopy
  • Stimulated emission depletion (STED) nanoscopy is a super-resolution fluorescence imaging technique to study biomolecular interactions in living systems at the highest possible temporal and spatial resolution. In this research, STED nanoscopy-based instrumentation will be advanced through implementation of ultrafast laser beam scanners and adaptive optics for suppression of aberrations. Moreover, novel data analysis tools based on single particle tracking and spatial/temporal correlations of pixel intensities will be developed and used for a range of biophysical experiments on living systems (cells, tissues organisms).


    Prof. Gerhard Paulus (Jena)
  • Strong-field laser physics
  • A central goal of molecular physics is to steer the outcome of chemical reactions. Ultrashort laser pulses provide a powerful tool to study and also control molecular bonds on ultrashort time scales. However, the interaction of molecules with laser pulses is governed by the excitation of bound or unbound electronic states, while most conventional chemistry proceeds on the electronic ground state via excitation of vibrational levels. Using ultrashort IR lasers, we strive to investigate the largely unexplored field of ground-state photochemistry. To this end, we use highly sophisticated laser technology as well as an advanced ion beam apparatus with time- and position-resolved coincidence detection. Available topics range from instrumentation and laser technology to data analysis and theoretical simulations.

  • Nanoscale XUV imaging
  • XUV radiation has distinctive advantages for imaging, including resolution and element-specific contrast. We recently invented XUV coherence tomography (XCT), which enables non-destructive cross-sectional imaging with nanoscale resolution. Available topics include the combination with other lens-less imaging modalities, ultrafast nanoscale imaging, and multispectral imaging.

  • Precision X-ray polarimetry
  • We have developed X-ray polarimeters providing extinction ratios of better than 1E-10, by far the best in the world and also by far beyond of what is possible in the optical regime. The ultimate goal is to measure the birefringence of vacuum polarized by a strong laser – and we believe that we have sufficiently advanced X-ray polarimetry to do such an experiment at the European XFEL in the next years. However, precision X-ray polarimetry offers a large range of other research opportunities. One of these is X-ray polarization microscopy. Another, in collaboration with Professor Röhlsberger, X-ray quantum optics.

  • Making molecular movies using coincidence spectroscopy
  • The ultimate goal of ultrafast molecular science is to make a movie that allows one to directly watch the motion of nuclei and electrons inside a molecule. Such a movie would provide microscopic insights into light-induced dynamics and chemical reactions that have thus far been inaccessible. Femtosecond laser pulses allow one to access the natural time scale of molecular dynamics. In this project, the potential film director will use a high-power, high-repetition rate femtosecond laser and combine it with a newly acquired coincidence imaging apparatus to record movies of electronic structure changes in molecules as they undergo dynamics.


    Prof. Thomas Pertsch (Jena)
  • Nanoscale photon control for next generation ultrafast integrated quantum systems
  • Nanoscale photon control for next generation ultrafast integrated quantum systems: We are looking for talented candidates, who are sharing the enthusiasm for nanoscale quantum photonics with us. This research field, with its multiple challenges in fundamental physics, quantitative modelling of complex multiphysics problems, nanotechnology, and experimental physics, is an ideal area for qualification of young scientists seeking career opportunities at the forefront of science & research. A PhD project in this field would involve the design, technological realization, and experimental characterization of nonlinear photonic nanostructures for photonic quantum state generation and detection. Besides curiosity-driven fundamental research in nanophotonics, the work would incorporate connections to application-driven projects for quantum imaging and sensing.


    Prof. Jürgen Popp (Jena)
  • Coherent biomedical Raman Imaging by means of ultrafast tunable laser sources
  • Novel Laser based techniques for imaging and spectroscopy, e.g., optical coherence tomography or coherent Raman imaging, are highly promising for biomedical applications. While techniques like stimulated Raman scattering put highest demands on the laser specifications, e.g., in terms of tuning range, tuning speed, bandwidth or noise, for successful clinical translation the laser systems have to be at the same time robust, compact and easy to use. In the group of Prof. Limpert custom-designed ultrafast fiber lasers are developed. Therefore, the aim of this work is to explore, adapt and apply novel laser concepts from the research group of Prof. Limpert (e.g., Fourier-domain mode locked lasers, four wave mixing frequency conversion) in biomedical imaging and spectroscopy, like hyperspectral coherent Raman imaging in the vibrational fingerprint region or multiplex coherent imaging of Raman tags. Furthermore, novel CARS excitation schemes for super resolution vibrational imaging beyond the Abbe limit utilizing the aforementioned laser sources should be explored.


    Prof. Nina Rohringer (Hamburg)
  • X-ray diffraction from population-inverted atoms: opportunities for single-particle imaging
  • X-rays provide a unique opportunity to obtain the structure of matter at atomic resolution. In crystals (periodic arrangement of atomic or molecular constituents) x-ray diffraction is successfully used over more than 100 years to unravel the atomic and electronic structure with applications ranging from simple materials to large biological complexes. Despite the advent of novel, ultrabright x-ray sources -- x-ray free-electron lasers (XFELs) -- the study of single particles of biological interest remains challenging. The challenge manifests itself in the inherently small elastic x-ray scattering strength (giving rise to diffraction) combined with strong competing processes such as ionization and/or Compton scattering. In this project, we will develop a novel imaging technique, relying on two-color pulses of XFELs: The first x-ray pulse will prepare atoms of the sample in core-excited states by promoting an electron of the inner-most electronic shell into a valence shell. The second x-ray pulse, tuned to an inner-shell transition (for example K- transition), will elastically scatter on a set of atoms in states of population inversion. Two effects will enhance the scattering signal: On resonance, anomalous x-ray scattering gives an enhancement of the scattering strength. Moreover, scattering on core-inverted atoms can result in stimulated emission, that eventually gives rise to an exponentially enhanced signal amplification. The signal from population-inverted atoms can be analyzed together with non-resonant scattering from other atoms of the object, thus enhancing the contrast. The successful candidate will develop the concept and theory of the novel approach and in the later stage of the project, will participate in proof-of-concept experiments at XFEL sources.


    Prof. Claus Ropers (Göttingen)
  • Development of Ultrafast Low-Energy Electron Microscopy
  • In this Project, a new concept for real-space imaging of ultrafast dynamics at surfaces is to be developed. We plan to integrate a pulsed photoemission electron source with a low-energy electron microscope. This will allow for the surface-sensitive mapping of ultrafast structural phase transitions, and the generation and propagation of collective excitations.


    Prof. Andreas Tünnermann (Jena)
  • High-dimensional quantum communication in tailored optical fibers
  • Path-encoded quantum bits have provided the basis for a myriad of proof-of-concept experiments in photonic quantum computing in the laboratory. As applications of quantum computers venture into the realm of distributed quantum information processing, a key challenge to be adressed ist he transmission of such states over long distances. Recent developments in multi-core fibers and tailored few-mode fibers would allow vast amounts of quantum infomration to be transmitted between distributed parties in a manner that is compatible with photonic quantum computing platforms.

  • Controlling the spatial structure of light for enhanced free-space optical communications and wave front sensing
  • Ultra-fast electro-optic switching technologies for heralded photon generation and feed-forward optical quantum information processing

  • Prof. Henry Chapman (Hamburg)
  • Lensless Imaging using Coherent Electrons
  • The methods of coherent diffractive imaging and ptychography replace a lens with an algorithm to obtain quantitative phase-sensitive images, and may provide advantages over conventional electron microscopy of macromolecules. This project will develop simulations of coherent electron diffraction under realistic conditions and compare with experiments, and investigate new algorithms to recover images from the diffraction data. We are looking for a candidate with a strong interest in imaging and Fourier optics, and who is capable of programming and performing data visualisation.

  • High resolution X-ray holography
  • One aspect of in-line holography is that the reference wave greatly amplifies the weak scattered wave from a small object such as a virus. With revolutionary new X-ray optics it becomes possible to record highly magnified in-line holograms of nanometer-sized objects. This project will explore the potentials of this for imaging biological materials, investigate the dose requirements, and experimentally demonstrate 3D imaging. The successful candidate should have a strong background in optics and imaging, and strong programming skills.

  • Time-resolved serial crystallography
  • This project will extend the method of serial femtosecond crystallography using X-ray free-electron lasers and synchrotron radiation facilities to investigate the dynamics of proteins induced by novel triggers, such as terahertz radiation or photo-acoustic waves. The candidate will have a unique opportunity to work on forefront research at advanced X-ray facilities as well as develop and test new experimental methods in the laboratory. The project combines experimental physics, structural biology, and computational analysis. We are therefore searching for a candidate with a strong interest in multidisciplinary research.


    Prof. Matthias Kling (Munich)
  • Attosecond imaging and spectroscopy of light-induced dynamics in molecules and nanostructures
  • We are interested in ultrafast correlated and collective electron dynamics that unfold when complex materials are exposed to intense, ultrashort laser fields. In particular this includes the attosecond control and tracing of strongly coupled electron-nuclear dynamics in quantum systems such as molecules, and of collective electron dynamics in nanostructured materials, and lightwave-driven petahertz (nano)electronics. We develop and use multi-dimensional imaging techniques in conjunction with (attosecond) pump-probe experiments to gain detailed insight into the dynamics from the interaction of these materials with near-single cycle laser fields of typically attosecond to femtosecond duration. We actively push the theoretical modeling of the rather complex multi-charge dynamics, which are partly carried out in our group using Monte-Carlo simulations with more intricate models within collaborations.


    Prof. Stefan Nolte (Jena)
  • Femtosecond inscribed chirped volume Bragg gratings
  • Volume Bragg gratings (VBGs) are a refractive index modulations within a transparent bulk material, having grating periods in the range of 1 µm, and act as a narrowband reflector. The gratings are inscribed by nonlinear absorption of femtosecond laser pulses, enabling the realization of VBGs in various types of glasses. Chirped VBGs, i.e. gratings with varying period over length, control the dispersive properties of the reflected signal, which can be utilized for pulse compression in chirped pulse amplification laser systems. The goal of this project is the realization of high power stable chirped VBGs by using femtosecond laser pulses to generate the refractive index modifications. The task is to further develop the inscription process from gratings with constant period to tailored profiles, providing excellent stability, ensuring the high power durability. Crucial is the control of the dispersive response for the successful application in pulse stretcher and compressor combinations.


    Prof. Gerhard Paulus (Jena)
  • Strong-field laser physics
  • A central goal of molecular physics is to steer the outcome of chemical reactions. Ultrashort laser pulses provide a powerful tool to study and also control molecular bonds on ultrashort time scales. However, the interaction of molecules with laser pulses is governed by the excitation of bound or unbound electronic states, while most conventional chemistry proceeds on the electronic ground state via excitation of vibrational levels. Using ultrashort IR lasers, we strive to investigate the largely unexplored field of ground-state photochemistry. To this end, we use highly sophisticated laser technology as well as an advanced ion beam apparatus with time- and position-resolved coincidence detection. Available topics range from instrumentation and laser technology to data analysis and theoretical simulations.

  • Nanoscale XUV imaging
  • XUV radiation has distinctive advantages for imaging, including resolution and element-specific contrast. We recently invented XUV coherence tomography (XCT), which enables non-destructive cross-sectional imaging with nanoscale resolution. Available topics include the combination with other lens-less imaging modalities, ultrafast nanoscale imaging, and multispectral imaging.

  • Precision X-ray polarimetry
  • We have developed X-ray polarimeters providing extinction ratios of better than 1E-10, by far the best in the world and also by far beyond of what is possible in the optical regime. The ultimate goal is to measure the birefringence of vacuum polarized by a strong laser – and we believe that we have sufficiently advanced X-ray polarimetry to do such an experiment at the European XFEL in the next years. However, precision X-ray polarimetry offers a large range of other research opportunities. One of these is X-ray polarization microscopy. Another, in collaboration with Professor Röhlsberger, X-ray quantum optics.


    Prof. Claus Ropers (Göttingen)
  • Development of Ultrafast Low-Energy Electron Microscopy
  • In this Project, a new concept for real-space imaging of ultrafast dynamics at surfaces is to be developed. We plan to integrate a pulsed photoemission electron source with a low-energy electron microscope. This will allow for the surface-sensitive mapping of ultrafast structural phase transitions, and the generation and propagation of collective excitations.


    Dr. Vladislav Yakovlev (Munich)
  • Theory of attosecond metrology in solids and nanoscale objects
  • All electronic devices are based on the coupled dynamics of charge carriers and electromagnetic fields. This synchronous motion has enabled many great advances in technology, from computing to telecommunications. How far are these technologies from their fundamental limits? We use both experiment and theory to find it out. Our research is centered upon this fundamental question: how to advance our ability to induce, control, and monitor charge-carrier dynamics with light? The Laboratory of Attosecond Physics specializes in the generation of precisely controlled light pulses in different spectral regions, from infrared to ultraviolet. The extraordinary degree of control over light, offered by our state-of-the-art laser sources, enables us to explore light-matter interaction taking place within a fraction of an oscillation cycle of a visible light field. Investigating such extremely fast processes, we pursue the vision of petahertz-scale optoelectronic signal processing.

  • The coupling of physics and photonics for the development of new technologies, applicable for bio-medical sciences.
  • Leveraging the controlled electric field transients available at the Max Planck Institute of Quantum Optic, that push the limits of current laser technology, to achieve temporal confinement of the ionization of molecular systems, we aim for complete temporal separation between the excitation and the resulting radiation. We are investigating the effects of rapidly removing an electron from a molecule using an impulse-like intense laser field and studying the radiation emitted from the resulting molecular ion, within the IR, mid-IR and THz spectral ranges. This work should have impact within the fields of THz science, spectroscopy, and bio-medical sciences.


    Prof. Stefan Hell (Göttingen)
  • Far-Field Optical Imaging at Molecular Resolution
  • New concepts have radically overcome the longstanding limits to optical analysis of molecular systems. Optical resolutions of a few nano¬meters have been demonstrated, well beyond Abbe’s diffraction limit, for example with the recent MINFLUX concept (Science 355, 606-612 (2017)). This opens up entirely new experimental opportunities, breaking new ground in the study of macromolecules and beyond. The successful candidate will develop advanced optical instrumentation and investigate physical imaging conditions and resolution performance. Alternatively, a related project involving theoretical optical analysis and modelling can be offered. The candidate should have (or expect to complete soon) a Master’s or equivalent degree in Physics or Physical Chemistry or a comparable qualification.


    Prof. David Hunger (Karlsruhe)
  • Label-free single-molecule sensing with open-access microcavities
  • The detection and characterization of individual non-fluorescent nanosystems with high temporal resolution could provide new insights into their intrinsic properties and dynamics. To achieve the high sensitivity required for studying individual unlabelled nanosystems in solution, we use signal enhancement in a fiber-based Fabry-Perot microcavity, which is integrated into a microfluidic channel. The presence and dynamics of a nanoobject in the tight focus of the cavity mode can be detected e.g. via the dispersive light-matter interaction and the resulting cavity frequency shift. Within the PhD project, measurement techniques shall be developed that achieve the sensitivity to reveal the Brownian motion of few-10-nm large nanoobjects at high temporal resolution. The goal is to investigate the polarizability of biologically relevant nanosystems and study their dynamical processes such as binding kinetics or folding dynamics.


    Prof. Ulrich Nienhaus (Karlsruhe)
  • Advanced Flourescence Microscopy
  • Stimulated emission depletion (STED) nanoscopy is a super-resolution fluorescence imaging technique to study biomolecular interactions in living systems at the highest possible temporal and spatial resolution. In this research, STED nanoscopy-based instrumentation will be advanced through implementation of ultrafast laser beam scanners and adaptive optics for suppression of aberrations. Moreover, novel data analysis tools based on single particle tracking and spatial/temporal correlations of pixel intensities will be developed and used for a range of biophysical experiments on living systems (cells, tissues organisms).


    Prof. Stefan Nolte (Jena)
  • Fs-laser induced cross-linking of corneal tissue
  • This highly interdisciplinary project is a collaboration with physicians and engineers of the universities in Göttingen and Jena to evaluate treatment scenarios using fs-laser induced cross-linking of corneal tissue. Possible applications are the treatment of keratoconus, or even refractive correction of myopia. Currently, the method of UV (A)-riboflavin crosslinking is used to stabilize the cornea in the keratoconus. Riboflavin is applied locally and cross-linked by UV (A) radiation. Yet, the precision of this procedure is low, and the exclusive treatment of diseased areas is not possible. In this project, fs-lasers should be used for the cross-linking of corneal collagen fibres. Using a high-speed scanner system, the focal spot of the fs-laser can be precisely controlled on the corneal surface allowing for a selective treatment of diseased areas.


    Prof. Jürgen Popp (Jena)
  • Coherent biomedical Raman Imaging by means of ultrafast tunable laser sources
  • Novel Laser based techniques for imaging and spectroscopy, e.g., optical coherence tomography or coherent Raman imaging, are highly promising for biomedical applications. While techniques like stimulated Raman scattering put highest demands on the laser specifications, e.g., in terms of tuning range, tuning speed, bandwidth or noise, for successful clinical translation the laser systems have to be at the same time robust, compact and easy to use. In the group of Prof. Limpert custom-designed ultrafast fiber lasers are developed. Therefore, the aim of this work is to explore, adapt and apply novel laser concepts from the research group of Prof. Limpert (e.g., Fourier-domain mode locked lasers, four wave mixing frequency conversion) in biomedical imaging and spectroscopy, like hyperspectral coherent Raman imaging in the vibrational fingerprint region or multiplex coherent imaging of Raman tags. Furthermore, novel CARS excitation schemes for super resolution vibrational imaging beyond the Abbe limit utilizing the aforementioned laser sources should be explored.


    Dr. Vladislav Yakovlev (Munich)
  • Theory of attosecond metrology in solids and nanoscale objects
  • Leveraging the controlled electric field transients available at the Max Planck Institute of Quantum Optic, that push the limits of current laser technology, to achieve temporal confinement of the ionization of molecular systems, we aim for complete temporal separation between the excitation and the resulting radiation. We are investigating the effects of rapidly removing an electron from a molecule using an impulse-like intense laser field and studying the radiation emitted from the resulting molecular ion, within the IR, mid-IR and THz spectral ranges. This work should have impact within the fields of THz science, spectroscopy, and bio-medical sciences.


    Prof. Nicolas Joly (Erlangen)
  • Photonic crystal fibres under pressure, one, two, three photons sources for quantum optics Photonics production

  • Prof. Bernhard Schmauß (Erlangen)
  • Optical frequency reflectometry based distributed spectroscopy

  • Dr. Birgit Stiller (Erlangen)
  • Light-sound interactions in the quantum domain
  • Optical waves interacting with acoustic or mechanic vibrations is a fascinating phenomenon because it links two very different domains in terms of frequency, velocity, dissipation and other properties. We explore these interactions experimentally at the classical and quantum level with suitably engineered microstructured fibres and nanowaveguides to manipulate, in this way, light states. Possible applications are a temporal memory for light, signal processing, high-sensitivity sensing and many more. The aim of this experimental PhD project is to explore the concepts of entanglement and squeezing via optoacoustic interaction. The topic is situated at the interface of quantum optics, nonlinear optics and quantum information processing. It involves conception and setup of fiber optical and chip-based experiments, photonic design (with option of fabrication) and numerical analysis and interpretation within the rich theoretical background.


    Dr. Hanieh Fattahi (Erlangen)
  • Generation of high energy, sub-cycle pulses
  • In this project, we employ state of the art high-energy, Yb:YAG thin disk lasers combined with broadband optical parametric amplifier and coherent field synthesis to generate sub-cycle pulses, or the so called light transients. High energy, optimised light transients allow to control nonlinear phenomena in sub-cycle regime (1,2). A good experience on developing lasers, handling ultrashort pulses, Labview and Matlab is beneficial for this position. 1."Multi-octave, CEP-stable source for high-energy field synthesis” A Alismail, H Wang, G Barbiero, …, H. Fattahi, Science advances 6 (7), eaax3408, 2020 2."Third-generation femtosecond technology", H Fattahi, HG Barros, M Gorjan, …, F. Krausz, Optica 1 (1), 45-63, 2014


    Prof. Matthias Kling (Munich)
  • Attosecond imaging and spectroscopy of light-induced dynamics in molecules and nanostructures
  • We are interested in ultrafast correlated and collective electron dynamics that unfold when complex materials are exposed to intense, ultrashort laser fields. In particular this includes the attosecond control and tracing of strongly coupled electron-nuclear dynamics in quantum systems such as molecules, and of collective electron dynamics in nanostructured materials, and lightwave-driven petahertz (nano)electronics. We develop and use multi-dimensional imaging techniques in conjunction with (attosecond) pump-probe experiments to gain detailed insight into the dynamics from the interaction of these materials with near-single cycle laser fields of typically attosecond to femtosecond duration. We actively push the theoretical modeling of the rather complex multi-charge dynamics, which are partly carried out in our group using Monte-Carlo simulations with more intricate models within collaborations.


    Prof. Jens Limpert (Jena)
  • Multi-pulse nonlinear pulse compression
  • Nonlinear pulse compression has become an irreplaceable technology that allows laser pulses from high-power laser systems to be temporally shortened so that they are suitable for numerous scientific applications in the field of high-field physics. This process can be realized either in gas-filled hollow-core fibers or in multi-pass cells. While both techniques have demonstrated massive performance advances in recent years, physical and practical limitations still pose a challenge. Today, more powerful laser systems are available than what these setups can handle. Parallelization in the form of coherent pulse combination has already been successfully applied for performance scaling of laser amplifiers. This concept should now be applied to nonlinear compression, especially focused on nonlinear multi-pass cells, which will pave a new path towards laser systems emitting few-cycle, high energy pulses at high average powers. The short pulse durations and associated broad optical bandwidths pose unique challenge, ranging from optics to control electronics. These will have to be addressed by novel approaches that will be developed in the frame of this thesis.


    Prof. Andreas Tünnermann (Jena)
  • High-dimensional quantum communication in tailored optical fibers
  • Path-encoded quantum bits have provided the basis for a myriad of proof-of-concept experiments in photonic quantum computing in the laboratory. As applications of quantum computers venture into the realm of distributed quantum information processing, a key challenge to be adressed ist he transmission of such states over long distances. Recent developments in multi-core fibers and tailored few-mode fibers would allow vast amounts of quantum infomration to be transmitted between distributed parties in a manner that is compatible with photonic quantum computing platforms.

  • Controlling the spatial structure of light for enhanced free-space optical communications and wave front sensing
  • Ultra-fast electro-optic switching technologies for heralded photon generation and feed-forward optical quantum information processing

  • Dr. Falk Eilenberger (Jena)
  • Lateral Heterostructures of semiconducting 2D-Materials in optical nanostructures
  • 2D-Materials are a highly interesting class of materials for optics and optoelectronic. Being direct semiconductors they can be utilized emit and detect light, if they are turned into diodes or transistors. Using advanced deposition techniques we mimic diodes and transistors by so-called lateral heterostructures, that is structures, where different types of 2D-semiconductore are directly attached to each other via a one-dimensional domain boundary. These boundaries have been shown to support light emission and detection, based on the recombination of excitons. In the project you shall explore the specific dynamics of such excitons at the one-dimensional interface and explore their potential for nano-scale lasing and/or single-photon detection. Moreover, lateral heterostructures of 2D-materials can grow directly on nano-patterned substrates, giving us leverage to combine their light emission properties with near-field active antenna-structures and integrated waveguide geometries simultaneously.


    Prof. Stefan Hell (Göttingen)
  • Far-Field Optical Imaging at Molecular Resolution
  • New concepts have radically overcome the longstanding limits to optical analysis of molecular systems. Optical resolutions of a few nano¬meters have been demonstrated, well beyond Abbe’s diffraction limit, for example with the recent MINFLUX concept (Science 355, 606-612 (2017)). This opens up entirely new experimental opportunities, breaking new ground in the study of macromolecules and beyond. The successful candidate will develop advanced optical instrumentation and investigate physical imaging conditions and resolution performance. Alternatively, a related project involving theoretical optical analysis and modelling can be offered. The candidate should have (or expect to complete soon) a Master’s or equivalent degree in Physics or Physical Chemistry or a comparable qualification.


    Prof. David Hunger (Karlsruhe)
  • Label-free single-molecule sensing with open-access microcavities
  • The detection and characterization of individual non-fluorescent nanosystems with high temporal resolution could provide new insights into their intrinsic properties and dynamics. To achieve the high sensitivity required for studying individual unlabelled nanosystems in solution, we use signal enhancement in a fiber-based Fabry-Perot microcavity, which is integrated into a microfluidic channel. The presence and dynamics of a nanoobject in the tight focus of the cavity mode can be detected e.g. via the dispersive light-matter interaction and the resulting cavity frequency shift. Within the PhD project, measurement techniques shall be developed that achieve the sensitivity to reveal the Brownian motion of few-10-nm large nanoobjects at high temporal resolution. The goal is to investigate the polarizability of biologically relevant nanosystems and study their dynamical processes such as binding kinetics or folding dynamics.


    Prof. Matthias Kling (Munich)
  • Attosecond imaging and spectroscopy of light-induced dynamics in molecules and nanostructures
  • We are interested in ultrafast correlated and collective electron dynamics that unfold when complex materials are exposed to intense, ultrashort laser fields. In particular this includes the attosecond control and tracing of strongly coupled electron-nuclear dynamics in quantum systems such as molecules, and of collective electron dynamics in nanostructured materials, and lightwave-driven petahertz (nano)electronics. We develop and use multi-dimensional imaging techniques in conjunction with (attosecond) pump-probe experiments to gain detailed insight into the dynamics from the interaction of these materials with near-single cycle laser fields of typically attosecond to femtosecond duration. We actively push the theoretical modeling of the rather complex multi-charge dynamics, which are partly carried out in our group using Monte-Carlo simulations with more intricate models within collaborations.


    Prof. Ulrich Nienhaus (Karlsruhe)
  • Advanced Flourescence Microscopy
  • Stimulated emission depletion (STED) nanoscopy is a super-resolution fluorescence imaging technique to study biomolecular interactions in living systems at the highest possible temporal and spatial resolution. In this research, STED nanoscopy-based instrumentation will be advanced through implementation of ultrafast laser beam scanners and adaptive optics for suppression of aberrations. Moreover, novel data analysis tools based on single particle tracking and spatial/temporal correlations of pixel intensities will be developed and used for a range of biophysical experiments on living systems (cells, tissues organisms).


    Prof. Stefan Nolte (Jena)
  • Spin-orbit photonics in inhomogeneous anisotropic media
  • In standard photonics light propagation is dictated by the refractive index gradient: photons behave as massive quantum particles under the action of a potential equal to the refractive index. Nonetheless, the behavior of photons can be far more complex, especially in the presence of exotic light-matter interaction. Here we aim to investigate the strong interaction between the spin (i.e., the light polarization) and the orbital (i.e., the wave vector) occurring when photons propagate in inhomogeneous anisotropic materials. In this regime light evolution recalls the propagation of charged particles in a magnetic field, and new effects are observed due to the gradients in the Pancharatnam-Berry phase. The fundamental nature and possible applications of spin-orbit phenomena will be both pursued, in the linear and nonlinear regime, including materials such as liquid crystals, light-written nanogratings in glass, two-photon polymerized structures and biased nanoguides in Lithium Niobate.


    Prof. Thomas Pertsch (Jena)
  • Nanoscale photon control for next generation ultrafast integrated quantum systems
  • Nanoscale photon control for next generation ultrafast integrated quantum systems: We are looking for talented candidates, who are sharing the enthusiasm for nanoscale quantum photonics with us. This research field, with its multiple challenges in fundamental physics, quantitative modelling of complex multiphysics problems, nanotechnology, and experimental physics, is an ideal area for qualification of young scientists seeking career opportunities at the forefront of science & research. A PhD project in this field would involve the design, technological realization, and experimental characterization of nonlinear photonic nanostructures for photonic quantum state generation and detection. Besides curiosity-driven fundamental research in nanophotonics, the work would incorporate connections to application-driven projects for quantum imaging and sensing.


  • Machine learning based design of nanostructured photonic metamaterials
  • Photonic metamaterials are a novel class of artificial matter consisting of building blocks, which are derived from sophisticated nanotechnologies and which have a mesoscopic size smaller than the wavelength of light. Metamaterials promise to obtain complete control over all classical, nonlinear, and quantum-optical properties characterizing light propagation. By designing the metamaterials´ unit cells one can tailor the linear and nonlinear light propagation in such media beyond the limits given by natural occurring materials. A focus of the PhD topic will lie in machine learning based algorithms for inverse design processes of novel nanomaterials. The project will evolve along the lines of simulation-based design of metamaterials, their practical realization using state-of-the-art lithography-based nanotechnologies, as well as their experimental characterization to close the loop for application-oriented optimization of resulting electromagnetic parameters.


    Prof. Carsten Rockstuhl (Karlsruhe)
  • Theoretical and Numerical Nanooptics
  • We study by analytical and numerical means the interaction of light in the linear, nonlinear, and quantum regime with nanostructured materials such as metals, semiconductors, dielectrics, or also molecular materials and explore applications thereof with different partners. Referential examples for such applications are, e.g., in the field of wave front shaping in integrated optical systems or for quantum sensing devices. We have activities in the field of plasmonics, optical nanoantannas, metamaterials and metasurfaces, computational material design (also known as solving the inverse problem), and quantum optics at the nanoscale in place and are currently seeking a PhD student to reinforce our team.


    Prof. Claus Ropers (Göttingen)
  • Development of Ultrafast Low-Energy Electron Microscopy
  • In this Project, a new concept for real-space imaging of ultrafast dynamics at surfaces is to be developed. We plan to integrate a pulsed photoemission electron source with a low-energy electron microscope. This will allow for the surface-sensitive mapping of ultrafast structural phase transitions, and the generation and propagation of collective excitations.


    Dr. Birgit Stiller (Erlangen)
  • Light-sound interactions in the quantum domain
  • Optical waves interacting with acoustic or mechanic vibrations is a fascinating phenomenon because it links two very different domains in terms of frequency, velocity, dissipation and other properties. We explore these interactions experimentally at the classical and quantum level with suitably engineered microstructured fibres and nanowaveguides to manipulate, in this way, light states. Possible applications are a temporal memory for light, signal processing, high-sensitivity sensing and many more. The aim of this experimental PhD project is to explore the concepts of entanglement and squeezing via optoacoustic interaction. The topic is situated at the interface of quantum optics, nonlinear optics and quantum information processing. It involves conception and setup of fiber optical and chip-based experiments, photonic design (with option of fabrication) and numerical analysis and interpretation within the rich theoretical background.


    Prof. Bernhard Schmauß (Erlangen)
  • Optical frequency reflectometry based distributed spectroscopy

  • Prof. Dr. Christine Silberhorn (Paderborn)
  • Multi-outcome quantum pulse gate for time-frequency high-dimensional quantum key distribution
  • High-dimensional quantum key distribution (HDQKD) promises an increase in both the security and secret key rates by going beyond a traditional qubit encoding. This excludes the use of polarization and - if we additionally require compatibility with integrated optics - spatial encodings. Information can be encoded in the time-frequency domain. Our group has shown that a quantum pulse gate (QPG) implements projective measurements onto arbitrary time-frequency bases. Yet, the current device design is limited to only one single measurement outcome; a limitation that makes it unsuitable for HDQKD. The goal of this project is to implement a multi-outcome QPG for time-frequency HDQKD with more than 10 dimensions. The research strategy will combine nonlinearity engineering, resonant structures, and temporal multiplexing, and will yield a high-performing plug-and-play device that is compatible with single-mode fibre.


    Dr. Maria Chekhova (Erlangen-Nürnberg)
  • Third-order parametric down-conversion
  • The goal is to experimentally observe a new nonlinear optical effect: direct decay of a photon in three, the inverse to the third harmonic generation. This effect, called third-order parametric down-conversion, is an upgrade of spontaneous parametric down-conversion (SPDC). It is far more unusual and interesting than SPDC: it results in quantum states of light with negative Wigner functions and it offers a realization of a cubic quantum gate, highly demanded in quantum information. Despite many theoretical works and several experimental attempts with nonlinear crystals, waveguides, and fibers, it has been not observed so far. In this PhD project the concept is to use a new class of materials, namely ultrathin layers with giant cubic nonlinearities (semiconductors, chalcogenide glass, metasurfaces) where phase matching will be not needed.

  • Loss-tolerant quantum imaging with twin beams
  • One of the ways to enhance signal-to-noise ratio in imaging is to illuminate an object with twin beams, for which the photon numbers are correlated. Such twin beams are produced at the output of a nonlinear crystal through high-gain parametric down-conversion. However, this technique is useless if the detection efficiency is not extremely high. The project aims at further developing this technique by adding phase sensitive parametric amplification of the image, which will make the imaging tolerant to any loss and therefore suitable for ‘difficult’ spectral ranges like IR and terahertz.


    Prof. David Hunger (Karlsruhe)
  • Realization of quantum nodes with rare earth ions in optical microcavities
  • Realization of quantum nodes with rare earth ions in optical microcavities: Rare earth ions doped into crystalline solids can show exceptional optical and hyperfine coherence, which makes them promising candidates for quantum optical applications ranging from quantum memories to quantum computing and sensing. The project will contribute to our activity on the efficient optical detection and quantum control of individual ions to realize optically addressable qubit registers. We use fiber-based microcavities to enhance optical transitions and high-resolution spectroscopy for selective addressing of ions.


    Prof. Nicolas Joly (Erlangen)
  • Photonic crystal fibres under pressure, one, two, three photons sources for quantum optics

  • Prof. Thomas Pertsch (Jena)
  • Nanoscale photon control for next generation ultrafast integrated quantum systems
  • Nanoscale photon control for next generation ultrafast integrated quantum systems: We are looking for talented candidates, who are sharing the enthusiasm for nanoscale quantum photonics with us. This research field, with its multiple challenges in fundamental physics, quantitative modelling of complex multiphysics problems, nanotechnology, and experimental physics, is an ideal area for qualification of young scientists seeking career opportunities at the forefront of science & research. A PhD project in this field would involve the design, technological realization, and experimental characterization of nonlinear photonic nanostructures for photonic quantum state generation and detection. Besides curiosity-driven fundamental research in nanophotonics, the work would incorporate connections to application-driven projects for quantum imaging and sensing.


    Prof. Nina Rohringer (Hamburg)
  • Source of entangled photon pairs and triplets via parametric down conversion in photonic crystals: opportunities from many-beam diffraction
  • Generation of entangled-photon pairs via parametric down-conversion (PDC) is an essential ingredient of numerous quantum-optics and quantum-information setups. To achieve the PDC generation, nonlinear response of the crystal in combination with phase-matching conditions is employed. The generation of entangled photon-triplets (for example, Greenberger–Horne–Zeilinger states) would provide further opportunities, however is even more challenging due to higher nonlinearities needed and further restrictions on phase-matching. In the current project, we propose to use photonic crystals (structures with artificially created spatial periodicity) to enhance the generation of PDC photons. Namely, we aim at a systematic exploration of the additional degrees of freedom emerging thanks to artificial periodicity (orientation of reciprocal lattice vectors) that can be used to steer the phase-matching conditions. The shaping of the electromagnetic field in the periodic structures (many-beam diffraction) was well-studied for x-rays and natural crystals. In this project, we aim at transferring the concepts from x-ray crystallography to photonic-crystals optics in order to find opportunities for enhanced production of entangled photons.


    Prof. Dr. Christine Silberhorn (Paderborn)
  • Multi-outcome quantum pulse gate for time-frequency high-dimensional quantum key distribution
  • High-dimensional quantum key distribution (HDQKD) promises an increase in both the security and secret key rates by going beyond a traditional qubit encoding. This excludes the use of polarization and - if we additionally require compatibility with integrated optics - spatial encodings. Information can be encoded in the time-frequency domain. Our group has shown that a quantum pulse gate (QPG) implements projective measurements onto arbitrary time-frequency bases. Yet, the current device design is limited to only one single measurement outcome; a limitation that makes it unsuitable for HDQKD. The goal of this project is to implement a multi-outcome QPG for time-frequency HDQKD with more than 10 dimensions. The research strategy will combine nonlinearity engineering, resonant structures, and temporal multiplexing, and will yield a high-performing plug-and-play device that is compatible with single-mode fibre.

  • Development of integrated nonlinear optical and electro-optical devices exploiting counter-propagating interactions in periodically poled waveguides with ultra-short poling periods
  • Future progress in the development in the emerging field of optical quantum technologies requires compact and miniaturized solutions for quantum circuits. Lithium niobate is proven to be a well-established material platform for numerous integrated quantum optical circuits. Recent progress in the technology for the fabrication of specifically tailored domain patterns with ultra-short poling periods will complement the portfolio of integrated functional elements in LiNbO3 for quantum applications. This project aims on the development of integrated nonlinear optical and electro-optical devices exploiting counter-propagating interactions in periodically poled waveguides with ultra-short poling periods. Among them can be photon-pair sources for the generation of decorrelated quantum states and electro-optically tuneable mirrors and polarization converters.


    Dr. Birgit Stiller (Erlangen)
  • Light-sound interactions in the quantum domain
  • Optical waves interacting with acoustic or mechanic vibrations is a fascinating phenomenon because it links two very different domains in terms of frequency, velocity, dissipation and other properties. We explore these interactions experimentally at the classical and quantum level with suitably engineered microstructured fibres and nanowaveguides to manipulate, in this way, light states. Possible applications are a temporal memory for light, signal processing, high-sensitivity sensing and many more. The aim of this experimental PhD project is to explore the concepts of entanglement and squeezing via optoacoustic interaction. The topic is situated at the interface of quantum optics, nonlinear optics and quantum information processing. It involves conception and setup of fiber optical and chip-based experiments, photonic design (with option of fabrication) and numerical analysis and interpretation within the rich theoretical background.


    Prof. Andreas Tünnermann (Jena)
  • High-dimensional quantum communication in tailored optical fibers
  • Path-encoded quantum bits have provided the basis for a myriad of proof-of-concept experiments in photonic quantum computing in the laboratory. As applications of quantum computers venture into the realm of distributed quantum information processing, a key challenge to be adressed ist he transmission of such states over long distances. Recent developments in multi-core fibers and tailored few-mode fibers would allow vast amounts of quantum infomration to be transmitted between distributed parties in a manner that is compatible with photonic quantum computing platforms.

  • Controlling the spatial structure of light for enhanced free-space optical communications and wave front sensing
  • Ultra-fast electro-optic switching technologies for heralded photon generation and feed-forward optical quantum information processing

  • Dr. Hanieh Fattahi (Erlangen)
  • Generation of high energy, sub-cycle pulses
  • In this project, we employ state of the art high-energy, Yb:YAG thin disk lasers combined with broadband optical parametric amplifier and coherent field synthesis to generate sub-cycle pulses, or the so called light transients. High energy, optimised light transients allow to control nonlinear phenomena in sub-cycle regime (1,2). A good experience on developing lasers, handling ultrashort pulses, Labview and Matlab is beneficial for this position. 1."Multi-octave, CEP-stable source for high-energy field synthesis” A Alismail, H Wang, G Barbiero, …, H. Fattahi, Science advances 6 (7), eaax3408, 2020 2."Third-generation femtosecond technology", H Fattahi, HG Barros, M Gorjan, …, F. Krausz, Optica 1 (1), 45-63, 2014


    Prof. Peter Hommelhoff (Erlangen)
  • Photonics-based electron control
  • We seek candidates for our particle accelerator on a chip experiment. After the successful demonstration of all required individual components, we now work towards building a particle accelerator on a photonic chip. Various avenues are possible, ranging from photonic structure design with modern tools such as inverse design to the investigation of quantum and non-linear phenomena.


    Prof. Matthias Kling (Munich)
  • Attosecond imaging and spectroscopy of light-induced dynamics in molecules and nanostructures
  • We are interested in ultrafast correlated and collective electron dynamics that unfold when complex materials are exposed to intense, ultrashort laser fields. In particular this includes the attosecond control and tracing of strongly coupled electron-nuclear dynamics in quantum systems such as molecules, and of collective electron dynamics in nanostructured materials, and lightwave-driven petahertz (nano)electronics. We develop and use multi-dimensional imaging techniques in conjunction with (attosecond) pump-probe experiments to gain detailed insight into the dynamics from the interaction of these materials with near-single cycle laser fields of typically attosecond to femtosecond duration. We actively push the theoretical modeling of the rather complex multi-charge dynamics, which are partly carried out in our group using Monte-Carlo simulations with more intricate models within collaborations.


    Prof. Stefan Nolte (Jena)
  • Femtosecond inscribed chirped volume Bragg gratings
  • Volume Bragg gratings (VBGs) are a refractive index modulations within a transparent bulk material, having grating periods in the range of 1 µm, and act as a narrowband reflector. The gratings are inscribed by nonlinear absorption of femtosecond laser pulses, enabling the realization of VBGs in various types of glasses. Chirped VBGs, i.e. gratings with varying period over length, control the dispersive properties of the reflected signal, which can be utilized for pulse compression in chirped pulse amplification laser systems. The goal of this project is the realization of high power stable chirped VBGs by using femtosecond laser pulses to generate the refractive index modifications. The task is to further develop the inscription process from gratings with constant period to tailored profiles, providing excellent stability, ensuring the high power durability. Crucial is the control of the dispersive response for the successful application in pulse stretcher and compressor combinations.

  • Spin-orbit photonics in inhomogeneous anisotropic media
  • In standard photonics light propagation is dictated by the refractive index gradient: photons behave as massive quantum particles under the action of a potential equal to the refractive index. Nonetheless, the behavior of photons can be far more complex, especially in the presence of exotic light-matter interaction. Here we aim to investigate the strong interaction between the spin (i.e., the light polarization) and the orbital (i.e., the wave vector) occurring when photons propagate in inhomogeneous anisotropic materials. In this regime light evolution recalls the propagation of charged particles in a magnetic field, and new effects are observed due to the gradients in the Pancharatnam-Berry phase. The fundamental nature and possible applications of spin-orbit phenomena will be both pursued, in the linear and nonlinear regime, including materials such as liquid crystals, light-written nanogratings in glass, two-photon polymerized structures and biased nanoguides in Lithium Niobate.

  • Photocatalysis for the synthesis of fuels and sustainable resources
  • The world faces tremendous challenges in environmental technology, as the emission of greenhouse gases has to be reduced rapidly and significantly to achieve climate goals. One of the main unsolved problems is the lack of technology for energy storage. A promising approach is the conversion of exhaust gases (CH4, CO, CO2, H2) to storable and transportable resources. Catalytic processes are the method of choice for this purpose, but it is difficult to trigger these reactions with thermal activation energy only. The present project should investigate the control of chemical reactions to produce fuels and sustainable resources using innovative laser technologies. Among these, coherent control using few-cycle pulses and pulse shaping will be applied to drive chemical reactions in the desired direction.

  • Fs-laser induced cross-linking of corneal tissue
  • This highly interdisciplinary project is a collaboration with physicians and engineers of the universities in Göttingen and Jena to evaluate treatment scenarios using fs-laser induced cross-linking of corneal tissue. Possible applications are the treatment of keratoconus, or even refractive correction of myopia. Currently, the method of UV (A)-riboflavin crosslinking is used to stabilize the cornea in the keratoconus. Riboflavin is applied locally and cross-linked by UV (A) radiation. Yet, the precision of this procedure is low, and the exclusive treatment of diseased areas is not possible. In this project, fs-lasers should be used for the cross-linking of corneal collagen fibres. Using a high-speed scanner system, the focal spot of the fs-laser can be precisely controlled on the corneal surface allowing for a selective treatment of diseased areas.


    Prof. Gerhard Paulus (Jena)
  • Strong-field laser physics
  • A central goal of molecular physics is to steer the outcome of chemical reactions. Ultrashort laser pulses provide a powerful tool to study and also control molecular bonds on ultrashort time scales. However, the interaction of molecules with laser pulses is governed by the excitation of bound or unbound electronic states, while most conventional chemistry proceeds on the electronic ground state via excitation of vibrational levels. Using ultrashort IR lasers, we strive to investigate the largely unexplored field of ground-state photochemistry. To this end, we use highly sophisticated laser technology as well as an advanced ion beam apparatus with time- and position-resolved coincidence detection. Available topics range from instrumentation and laser technology to data analysis and theoretical simulations.

  • Nanoscale XUV imaging
  • XUV radiation has distinctive advantages for imaging, including resolution and element-specific contrast. We recently invented XUV coherence tomography (XCT), which enables non-destructive cross-sectional imaging with nanoscale resolution. Available topics include the combination with other lens-less imaging modalities, ultrafast nanoscale imaging, and multispectral imaging.

  • Precision X-ray polarimetry
  • We have developed X-ray polarimeters providing extinction ratios of better than 1E-10, by far the best in the world and also by far beyond of what is possible in the optical regime. The ultimate goal is to measure the birefringence of vacuum polarized by a strong laser – and we believe that we have sufficiently advanced X-ray polarimetry to do such an experiment at the European XFEL in the next years. However, precision X-ray polarimetry offers a large range of other research opportunities. One of these is X-ray polarization microscopy. Another, in collaboration with Professor Röhlsberger, X-ray quantum optics.

  • Tailored Light-induced molecular potentials
  • The structure and dynamics of a molecule are governed by the forces between its nuclei and electrons. These forces give rise to the molecular potentials, on which nuclear motion and chemical reactions occur. Intense femtosecond laser fields can exert external forces comparable to the intermolecular ones. Thus, they can be used to manipulate molecular potentials on the timescales on the time scale of the nuclear dynamics. In this project, we will explore such routes to manipulate chemical reactions by means of tailored laser light.


    Dr. Vladislav Yakovlev (Munich)
  • Theory of attosecond metrology in solids and nanoscale objects
  • All electronic devices are based on the coupled dynamics of charge carriers and electromagnetic fields. This synchronous motion has enabled many great advances in technology, from computing to telecommunications. How far are these technologies from their fundamental limits? We use both experiment and theory to find it out. Our research is centered upon this fundamental question: how to advance our ability to induce, control, and monitor charge-carrier dynamics with light? The Laboratory of Attosecond Physics specializes in the generation of precisely controlled light pulses in different spectral regions, from infrared to ultraviolet. The extraordinary degree of control over light, offered by our state-of-the-art laser sources, enables us to explore light-matter interaction taking place within a fraction of an oscillation cycle of a visible light field. Investigating such extremely fast processes, we pursue the vision of petahertz-scale optoelectronic signal processing.

  • The coupling of physics and photonics for the development of new technologies, applicable for bio-medical sciences.
  • Leveraging the controlled electric field transients available at the Max Planck Institute of Quantum Optic, that push the limits of current laser technology, to achieve temporal confinement of the ionization of molecular systems, we aim for complete temporal separation between the excitation and the resulting radiation. We are investigating the effects of rapidly removing an electron from a molecule using an impulse-like intense laser field and studying the radiation emitted from the resulting molecular ion, within the IR, mid-IR and THz spectral ranges. This work should have impact within the fields of THz science, spectroscopy, and bio-medical sciences.


    Prof. Peter Hommelhoff (Erlangen)
  • Photonics-based electron control
  • We seek candidates for our particle accelerator on a chip experiment. After the successful demonstration of all required individual components, we now work towards building a particle accelerator on a photonic chip. Various avenues are possible, ranging from photonic structure design with modern tools such as inverse design to the investigation of quantum and non-linear phenomena.


    Prof. Stefan Karsch (Munich)
  • Development of ultralow-emittance electron beams for driving high-brilliance X-ray sources

  • Prof. Nicolas Joly (Erlangen)
  • Photonic crystal fibres under pressure, one, two, three photons sources for quantum optics

  • Prof. Heinrich Schleifenbaum (Aachen)
  • Interaction of laser radiation and polymers in Laser Sintering
  • Laser Sintering (LS) is a powder bed based Additive Manufacturing (AM) technology for the processing of polymer powders. To generate polymer parts with LS, CO2 lasers with a wavelength of 10.6 µm are used as standard, as the CO2 laser radiation is strongly absorbed by the polymer powders. In contrast, polymers hardly absorb any radiation in the near infrared (IR) at about 1 µm wavelength (e.g. fiber and diode laser radiation). In order to deepen research in this field, a fundamental understanding of the interaction of the laser radiation with different wavelengths and polymer materials must be developed. For this purpose, both the material itself as well as the interaction with the laser source have to be fundamentally investigated. Material combinations of polymers and absorber materials increase the absorption capacity at wavelengths of approximately 1 µm and offer the possibility to process polymers, but at the same time affect the resulting component properties. In addition, the fragile heat balance in LS (maximum variations of ±2-4°C) is to be analyzed with improved heating concepts in order to extend the knowledge gained on the processing of e.g. high-performance polymers such as PEEK with different radiation sources.

  • Simulation of the correlation between laser radiation and the polymer melting process in Laser Sintering
  • Nowadays, laser technology is used in many cases to melt materials. Especially in the field of Additive Manufacturing (AM) this is one of the most common processes (e.g. in Laser Sintering – LS). However, the exact interaction between the laser radiation and the molten material particles is not yet well understood. In view of the research into the processing of polymers by LS using laser beam sources with wavelengths that are insufficiently absorbed by the polymers, the sintering process must be analyzed in detail. The wavelength absorption as well as the conversion of the introduced energy to form sintered and molten polymer particles have not been sufficiently investigated so far. As a result, the formation of the molten material in correlation with the laser radiation, the formation of macro- and microscopic defects and the thermal behavior in x-, y- and z-direction must be studied. Therefore, different simulation methods (e.g. DEM, FEM) and monitoring equipment (e.g. pyrometers) will be further developed and applied to gain a fundamental understanding of the interaction between laser radiation and melting behavior, which will be calibrated and validated by iterative experiments.

  • Adaption of the chemical material composition for cross-layer crystallization in Laser Sintering
  • Laser sintering (LS) is a powder bed based additive manufacturing (AM) technology for the processing of polymers. Since LS is a layer-by-layer process in which the material is sintered and melted, the interconnection between the individual layers is of utmost importance to achieve the required stability of the component in the build-up direction. This could be achieved by increased crystallization of the material across the layers, requiring research into the adaption of the chemical composition of the polymer. Furthermore, to produce high-performance polymer components with LS, additives such as carbon or glass fibers are often added to the base material itself. During the melting process of the layers to each other, these fibers are interference bodies and reduce the layer bonding. Accordingly, the matrix material (base polymer) must achieve the required crystallization across the layers and therefore requires material adaptation which has to be investigated.


    Prof. Henry Chapman (Hamburg)
  • Lensless Imaging using Coherent Electrons
  • The methods of coherent diffractive imaging and ptychography replace a lens with an algorithm to obtain quantitative phase-sensitive images, and may provide advantages over conventional electron microscopy of macromolecules. This project will develop simulations of coherent electron diffraction under realistic conditions and compare with experiments, and investigate new algorithms to recover images from the diffraction data. We are looking for a candidate with a strong interest in imaging and Fourier optics, and who is capable of programming and performing data visualisation.

  • High resolution X-ray holography
  • One aspect of in-line holography is that the reference wave greatly amplifies the weak scattered wave from a small object such as a virus. With revolutionary new X-ray optics it becomes possible to record highly magnified in-line holograms of nanometer-sized objects. This project will explore the potentials of this for imaging biological materials, investigate the dose requirements, and experimentally demonstrate 3D imaging. The successful candidate should have a strong background in optics and imaging, and strong programming skills.

  • Time-resolved serial crystallography
  • This project will extend the method of serial femtosecond crystallography using X-ray free-electron lasers and synchrotron radiation facilities to investigate the dynamics of proteins induced by novel triggers, such as terahertz radiation or photo-acoustic waves. The candidate will have a unique opportunity to work on forefront research at advanced X-ray facilities as well as develop and test new experimental methods in the laboratory. The project combines experimental physics, structural biology, and computational analysis. We are therefore searching for a candidate with a strong interest in multidisciplinary research.


    Prof. Stefan Karsch (Munich)
  • Development of ultralow-emittance electron beams for driving high-brilliance X-ray sources

  • Prof. Matthias Kling (Munich)
  • Attosecond imaging and spectroscopy of light-induced dynamics in molecules and nanostructures
  • We are interested in ultrafast correlated and collective electron dynamics that unfold when complex materials are exposed to intense, ultrashort laser fields. In particular this includes the attosecond control and tracing of strongly coupled electron-nuclear dynamics in quantum systems such as molecules, and of collective electron dynamics in nanostructured materials, and lightwave-driven petahertz (nano)electronics. We develop and use multi-dimensional imaging techniques in conjunction with (attosecond) pump-probe experiments to gain detailed insight into the dynamics from the interaction of these materials with near-single cycle laser fields of typically attosecond to femtosecond duration. We actively push the theoretical modeling of the rather complex multi-charge dynamics, which are partly carried out in our group using Monte-Carlo simulations with more intricate models within collaborations.


    Prof. Nina Rohringer (Hamburg)
  • X-ray diffraction from population-inverted atoms: opportunities for single-particle imaging
  • X-rays provide a unique opportunity to obtain the structure of matter at atomic resolution. In crystals (periodic arrangement of atomic or molecular constituents) x-ray diffraction is successfully used over more than 100 years to unravel the atomic and electronic structure with applications ranging from simple materials to large biological complexes. Despite the advent of novel, ultrabright x-ray sources -- x-ray free-electron lasers (XFELs) -- the study of single particles of biological interest remains challenging. The challenge manifests itself in the inherently small elastic x-ray scattering strength (giving rise to diffraction) combined with strong competing processes such as ionization and/or Compton scattering. In this project, we will develop a novel imaging technique, relying on two-color pulses of XFELs: The first x-ray pulse will prepare atoms of the sample in core-excited states by promoting an electron of the inner-most electronic shell into a valence shell. The second x-ray pulse, tuned to an inner-shell transition (for example K- transition), will elastically scatter on a set of atoms in states of population inversion. Two effects will enhance the scattering signal: On resonance, anomalous x-ray scattering gives an enhancement of the scattering strength. Moreover, scattering on core-inverted atoms can result in stimulated emission, that eventually gives rise to an exponentially enhanced signal amplification. The signal from population-inverted atoms can be analyzed together with non-resonant scattering from other atoms of the object, thus enhancing the contrast. The successful candidate will develop the concept and theory of the novel approach and in the later stage of the project, will participate in proof-of-concept experiments at XFEL sources.

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