Annual Meeting Optical Society of America

Tunable squeezed-light generation from twin beams using an optical-phase feed-forward scheme: a broadband calculation

Chonghoon Kim, Prem Kumar

Published Jan 1, 1991• 0 citations

Abstract

Recently we analyzed an optical-phase feed-forward scheme to produce a squeezed-light beam from the twin beams generated by nondegenerate optical parametric amplification.1 Our interest in this scheme stems from the possibility it allows for the generation of tunable squeezed light. If the input signal beam to the parametric amplifier is tunable, a tunable squeezed output beam can be obtained for spectroscopic applications.2 In this paper we present a wideband model of this scheme. Noise characteristics of the homodyne detector, that measures squeezing properties of the phase-controlled output signal beam from the parametric amplifier, are analyzed in detail. To minimize the squeezed-noise power at an arbitrarily given sideband frequency, the optimal phase feed-forward transfer function is calculated. This feed-forward transfer function is achievable with a bandpass filter and an electronic amplifier. For certain frequency profiles of the gain and phase of the parametric amplifier, the squeezed-noise power spectral density can be minimized over the whole electronic bandwidth of the photodetector that is employed in homodyne detection.

DOI: 10.1364/oam.1991.mbb2

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