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Physical Review A

Continuous-variable Bell-type correlations from two bright squeezed beams

Elanor H. Huntington, Timothy C. Ralph

Published Dec 11, 2001• 7 citations
Publisher

Abstract

In this paper we propose two surprisingly simple optical systems that display Bell-type correlations between the continuous variables of their subsystems. We first discuss how these two systems may be used to construct Bell-type correlations from two bright, amplitude-squeezed sources. Then the experimental viability of these systems is analyzed. Issues such as the conditions under which the systems display Bell correlations, sources of nontechnical as well as technical noise, signal-to-noise ratio and losses are discussed. Based on this discussion, we conclude that both of these systems are currently experimentally viable.

DOI
10.1103/physreva.65.012306

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In this paper we propose two surprisingly simple optical systems that display Bell-type correlations between the continuous variables of their subsystems. We first discuss how these two systems may be used to construct Bell-type correlations from two bright, amplitude-squeezed sources. Then the experimental viability of these systems is analyzed. Issues such as the conditions under which the systems display Bell correlations, sources of nontechnical as well as technical noise, signal-to-noise ratio and losses are discussed. Based on this discussion, we conclude that both of these systems are currently experimentally viable.
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Summary form only given. Recently, a scheme for the generation of bright entangled beams has been suggested. The EPR-like quantum correlations are produced by letting two amplitude-squeezed bright optical fields interfere on a 50:50 beamsplitter. The phase (PM) and amplitude (AM) uncertainty measurements exhibit strong correlations and anticorrelations which can be detected by recording the difference (sum) of the PM (AM) photocurrents. In this paper we present a simple version of the quantum key distribution protocol. We believe that the suggested scheme provides an efficient and novel approach to continuous variable quantum communication.