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Sub-shot-noise heterodyne polarimetry

Sheng Feng·Olivier Pfister
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Abstract

We report the experimental demonstration of a heterodyne polarization rotation measurement with a noise floor 4.8 dB below the optical shot noise, by use of the classically phase-locked quantum twin beams emitted above threshold by an ultrastable type-II Na:KTP CW optical parametric oscillator. We believe this is the largest noise reduction achieved to date on optical phase-difference measurements.

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Sheng Feng, Olivier Pfister. 2004-08-19. Sub-shot-noise heterodyne polarimetry. https://doi.org/10.1364/ol.29.002800

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