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Quantum measurements of spatial conjugate variables: Displacement and tilt of a Gaussian beam

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

We consider the problem of measurement of optical transverse profile parameters and their conjugate variable. Using multi-mode analysis, we introduce the concept of detection noise-modes. For Gaussian beams, displacement and tilt are a pair of transverse profile conjugate variables. We experimentally demonstrate their optimal encoding and detection with a spatial homodyning scheme. Using higher order spatial mode squeezing, we show the sub-shot noise measurements for the displacement and tilt of a Gaussian beam.

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Vincent Delaubert, Nicolas Treps, Charles C. Harb, Ping Koy Lam, Hans A. Bachor. 2005-12-19. Quantum measurements of spatial conjugate variables: Displacement and tilt of a Gaussian beam. https://doi.org/10.1364/ol.31.001537

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