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arXiv · 1503.02854

Utilizing weak pump depletion to stabilize squeezed vacuum states

Timo Denker·Dirk Schütte·Maximilian H. Wimmer·Trevor A. Wheatley·Elanor H. Huntington·Michèle Heurs
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Abstract

We propose and demonstrate a pump-phase locking technique that makes use of weak pump depletion (WPD) - an unavoidable effect that is usually neglected - in a sub-threshold optical parametric oscillator (OPO). We show that the phase difference between seed and pump beam is imprinted on both light fields by the non-linear interaction in the crystal and can be read out without disturbing the squeezed output. Our new locking technique allows for the first experimental realization of a pump-phase lock by reading out the pre-existing phase information in the pump field. There is no degradation of the detected squeezed states required to implement this scheme.

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Timo Denker, Dirk Schütte, Maximilian H. Wimmer, Trevor A. Wheatley, Elanor H. Huntington, Michèle Heurs. 2015-03-10. Utilizing weak pump depletion to stabilize squeezed vacuum states. https://doi.org/10.1364/oe.23.016517

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