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arXiv · 0710.0053

High-sensitivity imaging with multi-mode twin beams

E. Brambilla·L. Caspani·O. Jedrkiewicz·L. A. Lugiato·A. Gatti
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Abstract

Twin entangled beams produced by single-pass parametric down-conversion (PDC) offer the opportunity to detect weak amount of absorption with an improved sensitivity with respect to standard techniques which make use of classical light sources. We propose a differential measurement scheme which exploits the spatial quantum correlation of type II PDC to image a weak amplitude object with a sensitivity beyond the standard quantum limit imposed by shot-noise.

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E. Brambilla, L. Caspani, O. Jedrkiewicz, L. A. Lugiato, A. Gatti. 2007-09-29. High-sensitivity imaging with multi-mode twin beams. https://doi.org/10.1103/physreva.77.053807

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