I. Physikalisches Institut - AG Mathias

Ultrafast Dynamics in Quantum Materials

Our research focuses on ultrafast electronic, magnetic, and structural dynamics in quantum materials, and the development of new experimental methods to study these processes. In particular, we combine the advantages of ultrashort X-rays from high-harmonic generation with ultrafast solid-state research, and explore dynamics at fundamental time- and lengthscales, where all elementary processes can be captured, even at the level of electrons. Current topics involve the study of electronic properties and dynamics in correlated-electron materials, at surfaces and interfaces, in nanostructures, and metal-adsorbate hybrid systems.

Research topics

• Ultrafast dynamics in 2D heterostructures of quantum materials
  
• Ultrafast magnetization dynamics in nanostructures
  
• Ultrafast electron dynamics at surfaces, interfaces, and in low-dimensional nanostructures
  
• Ultrafast x-ray materials science
  

News

02/2024 Our work on the hole-transfer during the build-up of interlayer excitons in 2d materials was published in Science Advances: Probing electron-hole Coulomb correlations in the exciton landscape of a twisted semiconductor heterostructure. Additionally, our work is featured on the cover of Science Advances:


English press release.

02/2024: Our historic collection of physics instruments "Physicalisches Cabinet" now has a virtual tour. Enjoy! For more details on the collection or to arrange a tour, visit the collection web page.

01/2024: Our group is organizing this year's Ultrafast Surface Dynamics 13 conference in Uslar, which is near to Göttingen, Germany. Focus research areas of the conference are: Dynamics in Quantum Materials; Ultrafast Magnetism; Lightwave Electronics; Floquet Engineering; Spatiotemporal Dynamics; Dynamics at Hybrid Interfaces; Ultrafast Plasmonics; Photo-induced Phase Transitions.

09/2023: Tim Titze was awarded a poster prize at IWCE 2023 in Göttingen. Congratulations!

09/2023: Wiebke Bennecke received the ECOSS PRIZE for the best oral presentation at the ECOSS, 36th European Conference on Surface Science. Congratulations!

07/2023: Two open PhD positions. We have two open PhD positions in our Momentum Microscopy Team and our Magneto-Optic Team:
Momentum Microscopy
Magneto-Optics

03/2023: Marcel Reutzel was selected to give a post-deadline talk at the DPG Spring Meeting in Dresden. Marcel Reutzel was selected to give a post-deadline talk about our work "Ultrafast nano-imaging of dark excitons". Congratulations!

02/2023: Jan Philipp Bange was awarded with the Poster Prize at the Lüscher-Wassermann-Seminar, Klosters, Switzerland. Congratulations!

02/2023: Christina Möller is "Physikerin der Woche 01/2023". Congratulations! Information on that event can be found at Physikerin der Woche 2023, DPG

11/2022: On the 25th of November the faculty is holding the Bachelorbörse. Information on that event can be found under Bachelor/Masters theses. A poster presenting an overview of the research topics of our group can also be found in the foyer of the physics faculty.

09/2022: Open position for PhD students on the projects " Time-resolved momentum microscopy on moiré heterostructures ", "Time- and spin-resolved momentum microscopy” and ”Time- and energy-resolved magneto-optical-Kerr spectroscopy”. For more information and to apply: see job describtion or contact Prof. Dr. Stefan Mathias.

08/2022 Our work on Moiré Interlayer Excitons has been published in Nature: Formation of Moiré Interlayer Excitons in Space and Time
The theory for the study was developed by the Malic group from Marburg University. Samples were fabricated in the Hofmann group, Cambridge University.
Picture: Brad Baxley, Part to Whole, LLC
Press Release of Göttingen University

01/2022 Open position for a PhD student on the project "Femtosecond Extreme Ultraviolet Spectromicroscopy" lead by Matthijs Jansen. For more information and to apply: https://www.uni-goettingen.de/de/305402.html?cid=16004 see job describtion

12/2021: On the 3rd of December the faculty is holding the (virtual) Bachelorbörse. Information on that event can be found under Bachelor/Masters theses. A poster presenting an overview of the research topics of our group can also be found in the foyer of the physics faculty.

11/2021: The German Science Foundation DFG funds our project "Spin- and time-resolved momentum microscopy for the study of ultrafast magnetism". The goal of the project is to study transient band-structure dynamics of optically-excited 3d ferromagnetic thin films. Have a look at our preliminary work: Band-structure evolution during demagnetization in Co (Science Adv., 2017).

11/2021: Wiebke Bennecke was awarded with the Poster Prize at the workshop Photoemission Tomography: Applications and Future Developments. Congratulations!

11/2021: New group leader looking for students
Matthijs Jansen has been offered a position as junior research group leader within CRC 1456. Are you interested to set up a femtosecond spectroscopy and microscopy experiment with close ties to materials science and data science? Then come by room B.02.123 or send a mail to gsmjansen @ uni-goettingen.de!



07/2021: CRC 1073 Atomic scale control of energy conversion" enters its third and final funding period!
Our group is participating with three projects in the A and B cluster of the CRC:

• Project A02: Understanding and manipulating relaxation channels to tailor energy transport
  
• Project B07: Elementary steps of energy conversion after a strong non-equilibrium excitation in correlated materials
  
• Project B10: Dissipation control of the (opto-)electronic properties of two-dimensional materials via controlled stacking and twisting
  

• Development of interferometrically time-resolved multi-photon photoemission; check out this article
  
• Electromagnetic dressing of solid-state band structures; check those articles: 1 & 2
  
• Energy dissipation in two-dimensional materials; check out this article
  
• Manipulating spin transfer on the shortest time scale; check out those articles: 1 & 2