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TEM10 homodyne detection as an optimal small displacement and tilt measurements scheme

Vincent Delaubert·Nicolas Treps·Mikael Lassen·Charles C. Harb·Claude Fabre·Ping Koy Lam·Hans A. Bachor
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Abstract

We report an experimental demonstration of optimal measurements of small displacement and tilt of a Gaussian beam - two conjugate variables - involving a homodyne detection with a TEM10 local oscillator. We verify that the standard split detection is only 64% efficient. We also show a displacement measurement beyond the quantum noise limit, using a squeezed vacuum TEM10 mode within the input beam.

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Vincent Delaubert, Nicolas Treps, Mikael Lassen, Charles C. Harb, Claude Fabre, Ping Koy Lam, Hans A. Bachor. 2006-07-20. TEM10 homodyne detection as an optimal small displacement and tilt measurements scheme. https://doi.org/10.1103/physreva.74.053823

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