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arXiv · 1603.07137

Time-delayed quantum coherent Pyragas feedback control of photon squeezing in a degenerate parametric oscillator

Manuel Kraft·Sven Moritz Hein·Judith Lehnert·Eckehard Schöll·Stephen Hughes·Andreas Knorr
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Abstract

Quantum coherent feedback control is a measurement-free control method fully preserving quantum coherence. In this paper we show how time-delayed quantum coherent feedback can be used to control the degree of squeezing in the output field of a cavity containing a degenerate parametric oscillator. We focus on the specific situation of Pyragas-type feedback control where time-delayed signals are fed back directly into the quantum system. Our results show how time-delayed feedback can enhance or decrease the degree of squeezing as a function of time delay and feedback strength.

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Manuel Kraft, Sven Moritz Hein, Judith Lehnert, Eckehard Schöll, Stephen Hughes, Andreas Knorr. 2016-03-23. Time-delayed quantum coherent Pyragas feedback control of photon squeezing in a degenerate parametric oscillator. https://doi.org/10.1103/physreva.94.023806

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