Research group of Prof. Dr. Stefan Mathias


We offer a wide range of bachelor and master projects, of which a few examples are listed below. If you are interested, feel free to write Prof. Stefan Mathias (smathias@uni-goettingen.de) or send an email to the responsible researcher for the project.

Dynamics in correlated materials



  • Optically induced phase transitions in 2D materials
  • Band structure dynamics in correlated oxides
  • Light-induced control of the electronic band structure

A possible project could be Moiré physics: Exploring correlated exciton phases in 2D heterostructures with time-resolved momentum microscopy. For more information, see the paper Time-resolved momentum microscopy with a 1 MHz high-harmonic extreme ultraviolet beamline and ask Jan Philipp Bange (janphilipp.bange@stud.uni-goettingen.de) for details.

Dynamics at interfaces and surfaces



  • Time- and angle-resolved two-photon photoemission from 2D materials
  • Interferometrically time-resolved multiphoton photoemission
  • Charge transfer in organic and 2D material heterostructures

A possible project could be Time-resolved photoemission orbital tomography on hybrid organic/2D material interfaces. For more information, see the papers Efficient orbital imaging based on ultrafast momentum microscopy and sparsity-driven phase retrieval and Tracing orbital images on ultrafast time scales. Ask Wiebke Bennecke (wiebke.bennecke@stud.uni-goettingen.de) for more details.

Another project is the construction and commissioning of an EUV monochromator with the aim of imaging 3-dimensional wave functions using orbital tomography. In particular, this enables the investigation of hybridized states at interfaces and the associated charge transfers. Another focus can be placed on the optimization of the required reconstruction algorithms, which is done in close cooperation with the mathematical faculty of the University of Göttingen. For more information, see Efficient orbital imaging based on ultrafast momentum microscopy and sparsity-driven phase retrieval and Exploring three-dimensional orbital imaging with energy-dependent photoemission tomography. Please contact Wiebke Bennecke (wiebke.bennecke@stud.uni-goettingen.de) for further details.

Ultrafast magnetization dynamics



  • Preparation of heterostructures of correlated oxides and metals
  • Photoinduced ferromagnetism in correlated materials
  • Electron, lattice- and spin dynamics in correlated ferromagnets

A possible project could be Element-resolved investigation of the magnetization dynamics of Fe and Ni in FeNi alloys or the implementation of hysteresis measurements in our EUV T-MOKE setup. For more information, see the paper Ultrafast element-resolved magneto-optics using a fiber-laser-driven extreme ultraviolet light source, and ask Matthijs Jansen (gsmjansen@uni-goettingen.de) for details.

Another possible project could be Investigating ultrafast demagnetization by spin-resolved photoemission momentum microscopy. For more information, see the papers Time-resolved momentum microscopy with a 1 MHz high-harmonic extreme ultraviolet beamline and Band structure evolution during the ultrafast ferromagnetic-paramagnetic phase transition in cobalt. For more details ask Sabine Steil (sabine.steil@phys.uni-goettingen.de).

We currently offer two projects in the field of time-resolved optical spectroscopy:

  1. Temperature-dependent analysis of an LSMO/LMCO superlattice in which the energy transport can be controlled by applying an external magnetic field.
  2. Investigation of the influence of different stabilization mechanisms on the dynamics of spin textures in multilayer metallic systems.

For details contact Tim Titze (tim.titze@uni-goettingen.de). Further projects can be offered here with a focus on certain materials, in the further development of the measurement setup or in data acquisition and analysis (focus: programming).

Method development: ultrafast X-rays



  • Element-resolved transient spectroscopy using high harmonics
  • Photoelectron diffraction using the momentum microscope
  • Wave function imaging from photoelectron spectroscopy data using phase retrieval

A possible project could be Transient EUV spectroscopy of 2D materials through interferometry. For more information, see the paper Spatially resolved Fourier transform spectroscopy in the extreme ultraviolet and ask Matthijs Jansen (gsmjansen@uni-goettingen.de).