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arXiv · 0907.3323

Homodyne locking of a squeezer

M. Heurs·I. R. Petersen·M. R. James·E. H. Huntington
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Abstract

We report on the successful implementation of a new approach to locking the frequencies of an OPO-based squeezed-vacuum source and its driving laser. The technique allows the simultaneous measurement of the phase-shifts induced by a cavity, which may be used for the purposes of frequency-locking, as well as the simultaneous measurement of the sub-quantum-noise-limited (sub-QNL) phase quadrature output of the OPO. The homodyne locking technique is cheap, easy to implement and has the distinct advantage that subsequent homodyne measurements are automatically phase-locked. The homodyne locking technique is also unique in that it is a sub-QNL frequency discriminator.

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M. Heurs, I. R. Petersen, M. R. James, E. H. Huntington. 2009-07-19. Homodyne locking of a squeezer. https://doi.org/10.1364/ol.34.002465

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