I am working in the field of non-equilibrium and nonlinear phenomena excited by terahertz (THz) electric fields in semiconductors. Terahertz physics and technology are one of the current frontiers in physics, bridging the gap between optics and microwave physics and holding great promise for progress in diverse scientific fields. The research objectives of our Terahertz Center at Regensburg University (TerZ) includes terahertz radiation induced photoelectric phenomena, terahertz spin dependent phenomena, tunneling processes in high-frequency fields, nonlinear absorption of radiation, nonlinear optics in the classical sense, hot electron dynamics, ponderomotive action of the radiation field on a free electron gas as well as the development of novel terahertz detectors and components. Most of the experimental work has been devoted to intense excitation of semiconductors exploring a great variety of new basic physics and yielding data on the dynamics of carriers valuable for applications and the development of devices.
Today the focus of my research is on:

• the physics around THz opto-electronic phenomena in various Dirac Fermions systems including two- and three-dimensional topological insulators and graphene
• Ratchet effects in two-dimensional structures with lateral superlattices
• Terahertz radiation induced electron-, spin- and magneto-transport phenomena in semiconductor quantum well structures