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Limits to phase information in the parametric oscillator

P. Kinsler
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Abstract

Light in which the quantum fluctuations have been squeezed is often proposed as a means of obtaining an improved phase reference compared to that available from coherent light. Such a phase reference contains information about the phase of the squeezed light, so it is important to calculate the limits to the amount of ``phase information'' available. I define a phase resolution and show how this scales as we increase the number of photons available when using squeezed light generated by a parametric oscillator. Simple schemes for creating squeezed coherent light using a beam-splitter and an interferometer are analyzed, and it is shown that the results agree with earlier claims [Kinsler] that when using squeezed coherent light as a phase reference, the gain is not one of improved accuracy, but of lower power.

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P. Kinsler. 2001-10-19. Limits to phase information in the parametric oscillator. https://arxiv.org/abs/quant-ph/0110118

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