Transient negative cyclotron absorption due to partially‐inverted distribution of photoexcited electrons

Abstract

The transient magnetoresponse of electrons with partially‐inverted distribution excited by an ultrashort optical pulse in bulk GaAs and InSb is considered. A huge transient amplification of a probe microwave or THz field due to negative cyclotron absorption is described using the kineticequation and the wave equation. A quantum picture of THz emission due to transitions between the Landau levels with different broadenings is suggested. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)