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Sub shot noise phase quadrature measurement of intense light beams

O. Glöckl·U. L. Andersen·S. Lorenz·Ch. Silberhorn·N. Korolkova·G. Leuchs
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Abstract

We present a setup to perform sub shot noise measurements of the phase quadrature for intense pulsed light without the use of a separate local oscillator. A Mach--Zehnder interferometer with an unbalanced arm length is used to detect the fluctuations of the phase quadrature at a single side band frequency. Using this setup, the non--separability of a pair of quadrature entangled beams is demonstrated experimentally.

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O. Glöckl, U. L. Andersen, S. Lorenz, Ch. Silberhorn, N. Korolkova, G. Leuchs. 2004-06-14. Sub shot noise phase quadrature measurement of intense light beams. https://doi.org/10.1364/ol.29.001936

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