Stimulated emission using the transitions of shallow acceptor states in germanium

Abstract

Discrete lines with frequencies corresponding to the optical transitions from the excited states to the ground state of an acceptor impurity have been observed in the spectra of a FIR p-Ge laser, which operates on hole intersubband transitions in crossed electric and magnetic fields. Stimulated emission on impurity transitions arises due to the redistribution of holes in the nonlinear mode of laser generation. A gain mechanism on these transitions is discussed. It is also observed that these lines are tuned under the uniaxial stress on an active p-Ge crystal.