Optical investigation of bloch oscillations in semiconductor superlattices

Abstract

We investigate the dephasing dynamics in semiconductor superlattices using time-resolved four-wave mixing. The signals show a periodic modulation which can be related to Bloch oscillations in the superlattice miniband. The oscillation frequency is strongly dependent on the applied field, in agreement with theoretical expectation. At high fields, the dephasing times become very short due to field-induced scattering. © 1993 Academic Press.