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arXiv · 2204.02367

Embedding of Time-Delayed Quantum Feedback in a Nonreciprocal Array

Xin H. H. Zhang·S. H. L. Klapp·A. Metelmann
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Abstract

Time-delayed quantum feedback is a fast and efficient method to control and stabilize few and many-body quantum systems. However, a proper understanding of such systems stays opaque due to the non-Markovian nature of the feedback protocol. Here, we present a method of encoding time-delayed quantum feedback into a chain of nonreciprocally coupled auxiliary oscillators. Our approach serves as a novel method of introducing time-delayed quantum feedback and provides the advantage of large tunability. Importantly, within our approach the original non-Markovian system is embedded into an enlarged Markovian open quantum system, which can be treated efficiently with quantum many-body methods. As an exemplary illustration, we apply our Markovian embedding approach to the paradigmatic case of a driven-dissipative atom in front of a mirror.

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Xin H. H. Zhang, S. H. L. Klapp, A. Metelmann. 2022-04-05. Embedding of Time-Delayed Quantum Feedback in a Nonreciprocal Array. https://arxiv.org/abs/2204.02367

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