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Physical Review A

Theory of the quantum-beat laser

Marlan O. Scully, Muhammad Suhail Zubairy

Published Jan 1, 1987• 180 citations
Publisher

Abstract

A theory of the quantum-beat laser is developed using a general Fokker-Planck approach. An explicit expression for the diffusion coefficient for the relative phase angle of the two modes is derived. It is shown that the diffusion coefficient can vanish under certain conditions.
DOI
10.1103/physreva.35.752

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We calculate the phase-difference and phase-sum fluctuations of the quantum-beat laser, using the nonlinear model of Bergou et al. [Phys. Rev. A 38, 754 (1988)], and also making use of the phase operators defined by Pegg and Barnett [Phys. Rev. A 39, 1665 (1989)]. We found a vanishing phase-difference diffusion constant, in agreement with Bergou et al. However, the present formalism is more general, and includes shot noise as well as saturation effects for the relative and sum phase fluctuations.
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