Search Results
Ultrafast two-dimensional terahertz spectroscopy of elementary excitations in solids
2013, Woerner, M., Kuehn, W., Bowlan, P., Reimann, K., Elsaesser, T.
Recent experimental progress has allowed for the implementation of nonlinear two-dimensional (2D) terahertz (THz) spectroscopy in the ultrafast time domain. We discuss the principles of this technique based on multiple phase-locked electric field transients interacting in a collinear geometry with a solid and the phase-resolved detection of the THz fields after interaction with the sample. To illustrate the potential of this new method, 2D correlation spectra of coupled intersubband-longitudinal optical phonon excitations in a double quantum well system and a study of ultrafast carrier dynamics in graphene are presented.
Transition from ballistic to drift motion in high-field transport in GaAs
2013, Bowlan, P., Kuehn, W., Reimann, K., Woerner, M., Elsaesser, T., Hey, R., Flytzanis, C.
With strong THz pulses, we measure ultrafast transport of electrons, holes, and an electron-hole plasma in GaAs. The transition from ballistic to drift-like transport is strongly influenced by electron-hole scattering.