Ultrafast infrared and THz spectroscopy of semiconductor quantum structures

This talk gives an overview on our activities in nonlinear laser spectroscopy using the free-electron laser at FZD and tabletop lasers. Our research concentrates on III-V semiconductor quantum wells and superlattices. In particular, I will discuss two-photon absorption and photocurrent autocorrelation involving intersubband transitions in quantum wells at mid-infrared wavelengths.