Optically induced femtosecond electromagnetic pulses from GaSb/AlSb strained-layer superlattices

Abstract

The strain generated electric field in a 〈111〉 oriented misfit superlattice provides a suitable bias for generating optically induced femtosecond electromagnetic radiation. We have measured the electromagnetic radiation from GaSb/AlSb strained-layer superlattices and GaSb thin films; extremely fast electromagnetic pulses from 〈111〉 oriented superlattices have been observed. Because the quantum well structure in the superlattice samples limits the pulse duration of the transient photocurrent, it is possible to generate electromagnetic radiation having a pulse duration comparable with the photocarrier transit time across the quantum well.