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Does Excess Quantum Noise Exist in Spontaneous Processes?

A. Aiello·M. P. van Exter·G. Nienhuis·J. P. Woerdman
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Abstract

We investigate the role of excess quantum noise in type-II degenerate parametric down conversion in a cavity with non-orthogonal polarization eigenmodes. Since only two modes are involved we are able to derive an analytical expression for the twin-photon generation rate measured outside the cavity as a function of the degree of mode nonorthogonality. Contrary to recent claims we conclude that there is no evidence of excess quantum noise for a parametric amplifier working so far below threshold that spontaneous processes dominate.

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A. Aiello, M. P. van Exter, G. Nienhuis, J. P. Woerdman. 2002-06-07. Does Excess Quantum Noise Exist in Spontaneous Processes?. https://doi.org/10.1016/s0030-4018(02)01995-8

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