Paper 145 Abstract

IEEE Journal of Quantum Electronics 32, pp. 1995-2003 (1996)

Theory of gain spectra for quantum cascade lasers
and temperature dependence of their characteristics
at low and moderate carrier concentrations

Vera Gorfinkel and Serge Luryi
Department of Electrical Engineering
State University of New York at Stony Brook
Stony Brook, NY 11794-2350

Boris Gelmont
Department of Electrical Engineering
University of Virginia
Charlottesville, VA 22903-2442


We have developed a theory describing the operation of lasers based on intersubband transitions in a quantum well. The theory combines a first-principles description of the intersubband lineshape and the optical gain with kinetic models for carrier heating. The theory is consistent with the experimental data available and suggests new ways of improving the laser design for room temperature operation with high output power. At low carrier concentrations, it is possible to achieve positive values of the gain at room temperature even in the absence of an overall population inversion between quantum well subbands. For higher (but still moderate) concentrations, the theory predicts a peculiar dependence of the output wavelength on the pump current, including a regime where the lasing wavelength switches "digitally" between two stable values.

Download full text (PDF, 800 kB)

Return to [ 1994-96 Publication Record] home page Return to the [Publication Record] home page

Return to the [Serge Luryi's] home page

Return to the [Faculty] Home Page

Return to the [EE Department] home page

Serge Luryi,, +1.631.632.8420; Fax: +1.631.632.8494