Electron-beam-controlled transmission of 10-μm radiation in semiconductors

Abstract
An electron beam has been used to control the transmission of 10.6‐μm radiation in Ge, ZnSe, and CdTe samples. With an ∼2.5‐A/cm2 20‐ns pulse of ∼110‐keV electrons incident on the semiconductor, the transmission falls abruptly, recovering in approximately the recombination time of the semiconductor. Carrier‐absorption cross sections at 10.6 μm have been determined for CdTe and ZnSe. Semiconductor transmission switching provides a broad‐bandwidth active isolator which may find applications in high‐gain CO2 laser systems.