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Nonlinear Interferometry via Fock State Projection

G. Khoury·H. S. Eisenberg·E. J. S. Fonseca·D. Bouwmeester
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Abstract

We use a photon-number resolving detector to monitor the photon number distribution of the output of an interferometer, as a function of phase delay. As inputs we use coherent states with mean photon number up to seven. The postselection of a specific Fock (photon-number) state effectively induces high-order optical non-linearities. Following a scheme by Bentley and Boyd [S.J. Bentley and R.W. Boyd, Optics Express 12, 5735 (2004)] we explore this effect to demonstrate interference patterns a factor of five smaller than the Rayleigh limit.

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G. Khoury, H. S. Eisenberg, E. J. S. Fonseca, D. Bouwmeester. 2006-05-22. Nonlinear Interferometry via Fock State Projection. https://doi.org/10.1103/physrevlett.96.203601

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