Abstract

In the last few years there has been substantial interest in the lasers capable of operation without inversion (LWI). Numerous schemes have been suggested [1],[2], which, if realized in practice, can expand the range of laser devices in spectral regions where for various reasons inversion is difficult to achieve - among them vacuum UV, using atomic vapors as an active medium, and mid-to-far IR., using intersubband transitions in quantum wells. Until recently, the research has been mostly limited to the theoretical work, but lately there had been a conclusive report of laser oscillation without inversion in Rb [3]. A number of LWI proposals based on intersubband transitions in quantum wells, that seem to be ideally suited for the practical implementation of LWI concept, have also been made.

© 1996 Optical Society of America