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Soviet Journal of Quantum Electronics

Investigation of the parameters of a fiber optical quantum image amplifier

V L Koval'chuk, V P Konarev, V N Lomakin, I. N. Matveev

Published Apr 30, 1977• 1 citation
Publisher

Abstract

An experimental investigation was made of the resolution of a neodymium-activated glass fiber laser image amplifier and of the dependence of the signal/noise ratio at the amplifier output on the signal power at the input. The resolution in the active regime (in the presence of pumping) was not inferior to that in the passive regime (without pumping) and the signal/noise ratio (and, consequently, the contrast of the amplified image) improved, compared with the passive regime.

DOI
10.1070/qe1977v007n04abeh009758

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The concept of noise figure F and noise measure M applicable to radio frequency and microwave amplifiers is reviewed and extended to cover optical amplifiers. Two noise figures are defined in the optical regime: one gives the ASE output, while the other gives the ratio of signal-to-noise ratios at the input and output. In the quantum regime, the lower limit on these optimum values is set by a generalization of Heisenberg's uncertainty relation. A Raman back-pumped fiber link with post-amplification with an erbium-doped fiber amplifier is used to illustrate the use of noise measure.
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