Abstract

Semiconductor lasers based on band-to-band transitions in the far infrared are of great interest since they promise kW power, multioctave tunability and sub-ps pulse length in a traditionally power-starved spectral region.^[1] Several aspects are well understood such as the electrical acceleration, the magnetic confinement, and the collision dynamics of active holes. A direct gain measurement that could test theoretical models has however not yet succeeded, because of the smallness of the gain and the problems of optically accessing a highly reflecting crystal in a cryomagnet.

© 1992 IQEC