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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Non-stationary entanglement and squeezing beyond the standard limits

Hayk H. Adamyan, Gagik Yu. Kryuchkyan

Published May 24, 2006• 0 citations
Publisher

Abstract

We investigate time-modulation of continuous variable (CV) quantum states of light fields in application to time-resolved quantum communications. As realizations, we consider EPR entangled states of light as well as correlated twin beams generated in nondegenerate optical parametric oscillator (NOPO) subjected by a sequence of laser pulses. We demonstrate that time-modulation of a pump field essentially improves the degrees of both cv entanglement and intensity quantum correlation in NOPO doing them beyond the standard limits.

DOI
10.1117/12.683118

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Quantum entanglement and intensity correlations in continuous variable (CV) regimes have investigated in the time domain in addition to many analogous investigations performed in the frequency domain. The specific signatures of time-resolved CV quadrature entanglement and intensity difference squeezing have been analyzed for periodically-pulsed optical parametric oscillator (OPO). An application to quantum key distribution scheme based on intensity correlation of twin beams has also been considered.