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Quantum Langevin theory of excess noise

P. J. Bardroff·S. Stenholm
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Abstract

In an earlier work [P. J. Bardroff and S. Stenholm], we have derived a fully quantum mechanical description of excess noise in strongly damped lasers. This theory is used here to derive the corresponding quantum Langevin equations. Taking the semi-classical limit of these we are able to regain the starting point of Siegman's treatment of excess noise [Phys. Rev. A 39, 1253 (1989)]. Our results essentially constitute a quantum derivation of his theory and allow some generalizations.

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P. J. Bardroff, S. Stenholm. 1999-04-14. Quantum Langevin theory of excess noise. https://doi.org/10.1103/physreva.61.023806

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