High-power ultrashort pulse laser system for simultaneous generation of ultrashort THz-pump and VUV-probe pulses

• Subject Area: Condensed Matter Physics
• Term: Funded in 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 445487514

The requested high-power ultrashort pulse laser system together with a tailored vacuum ultraviolet source should provide phase-stable subcycle pump pulses in the multi-THz spectral domain and vacu-um ultraviolet probe pulses with photon energies between 20 and 30 eV at repetition rates between 10 and 200 kHz.Based on our recent experiments on subcycle-APRES (angle-resolved photoemission spectroscopy), the new system should be employed to make the first-ever femtosecond-slow-motion film of lightwave-driven electrons in the band structure of a solid over the entire first Brillouin zone. In a wide variety of modern quantum materials like graphene, transition metal dichal-cogenides or surface states of topological insulators, novel aspects of ultrafast electron dynamics should be mapped out, on the relevant time and energy scales. Examples are the observation of Bloch oscillations and the ultrafast switching of the valley pseudospin or the investigation of strongly corre-lated electron systems, in the band structure of the underlying solids. Additionally, the highly stable laser system with a high repetition rate is necessary to measure the weak signals that occur in high harmonic generation in atomically thin solids or surface states of topological insulators. During these experiments, we want to study lightwave electronics and spintronics on topological insulators, by Erwin Schrödinger theoretically predicted Zitterbewegung and the effects of topologically non-trivial quantum paths. Finally, the new laser source should also be used to investigate theoretically predicted effects in non-adiabatic cavity quantum electrodynamics similar to Unruh-Hawking radiation of black holes.The requested laser source is a strategic key element for the exploration of emergent relativistic ef-fects in condensed matter at the University of Regensburg. The experiments are, thus, especially rele-vant for the Collaborative Research Center and numerous bilateral interdisciplinary collabora-tions.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Hochleistungsultrakurzpuls-Lasersystem zur synchronen Erzeugung ultrakurzer THz-Pump- und VUV-Abtastimpulse
• Instrumentation Group: 5700 Festkörper-Laser
• Applicant Institution: Universität Regensburg
• Leader: Professor Dr. Rupert Huber