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arXiv · 0812.2142

Quantum limits in the measurement of very small displacements in optical images

Claude Fabre·J. -B. Fouet·Agnès Maître
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Abstract

We consider the problem of the measurement of very small displacements in the transverse plane of an optical image with a split photodetector. We show that the standard quantum limit for such a measurement, which is equal to the diffraction limit divided by the square root of the number of photons used in the measurement, cannot be overcome by use of ordinary single-mode squeezed light. We give the form of possible multimode nonclassical states of light, enabling us to enhance by orders of magnitude the resolution of such a measurement beyond the standard quantum limit.

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Claude Fabre, J. -B. Fouet, Agnès Maître. 2008-12-11. Quantum limits in the measurement of very small displacements in optical images. https://doi.org/10.1364/ol.25.000076

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