Annual Meeting Optical Society of America

Lasing without inversion—gain enhancement with a colored pump

Gautam Vemuri, G. S. Agarwal, THOMAS W. MOSSBERG

Published Jan 1, 1993• 0 citations

Abstract

Most models of lasing without inversion utilize incoherent pumping of the upper state of the transition on which lasing occurs. We suggest replacing incoherent pumping by a color pump (i.e. laser with a finite bandwidth) for selective pumping of the upper state, where one can also take advantage of the tunability of the laser. A three-level ladder system is considered with the upper two levels providing the lasing transition. We reduce the density matrix equations for this system to a set of eight coupled Langevin equations with multiplicative noise. These equations are solved using Monte-Carlo methods to obtain the gain as a function of various atom and field parameters. The use of the color pump leads to a significant enhancement in gain. Using a dressed states formalism, an explanation of the possible physical mechanism behind this gain enhancement is provided.

DOI: 10.1364/oam.1993.thq.6

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