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IEEE Journal of Quantum Electronics

Autocorrelation function for thermal noise in the case of maser amplifiers

Renuka Jindal, Aldert van der Ziel

Published Feb 1, 1981• 1 citation
Publisher

Abstract

This paper gives the autocorrelation function of thermal noise when the zero point energy noise term is neglected. Such a situation applies to maser amplifiers.
DOI
10.1109/jqe.1981.1071084

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The contribution of the saturation field to the noise figure of a three-level maser is calculated. It is shown that the effect is very small, under ordinary circumstances.Certain aspects of spontaneous-emission noise are considered. It is shown that the spontaneous-emission equivalent temperature for a free-electron vacuum-tube amplifier is one-half that of a maser.The possibility of eliminating spontaneous-emission noise is considered and it is concluded that more general quantum-mechanical amplifiers can in principle be constructed which will not have spontaneous-emission noise.