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Quantum interference of ultrastable twin optical beams

Sheng Feng·Olivier Pfister
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Abstract

We report the first measurement of the quantum phase-difference noise of an ultrastable nondegenerate optical parametric oscillator that emits twin beams classically phase-locked at exact frequency degeneracy. The measurement illustrates the property of a lossless balanced beam-splitter to convert number-difference squeezing into phase-difference squeezing and, thus, provides indirect evidence for Heisenberg-limited interferometry using twin beams. This experiment is a generalization of the Hong-Ou-Mandel interference effect for continuous variables and constitutes a milestone towards continuous-variable entanglement of bright, ultrastable nondegenerate beams.

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Sheng Feng, Olivier Pfister. 2004-03-26. Quantum interference of ultrastable twin optical beams. https://doi.org/10.1103/physrevlett.92.203601

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