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arXiv · 2110.07942

Designing optimal linear detectors -- a bottom-up approach

Joe Bentley·Hendra Nurdin·Yanbei Chen·Xiang Li·Haixing Miao
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Abstract

This paper develops a systematic approach to realising linear detectors with an optimised sensitivity, allowing for the detection of extremely weak signals. First, general constraints are derived on a specific class of input-output transfer functions of a linear detector. Then a physical realization of transfer functions in that class is found using the quantum network synthesis technique, which allows for the inference of the physical setup directly from the input-output transfer function. By exploring a minimal realization which has the minimum number of internal modes, it is shown that the optimal such detectors are internal squeezing schemes. Then, investigating non-minimal realizations, which is motivated by the parity-time symmetric systems, a quantum non-demolition measurement is systematically recovered.

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Joe Bentley, Hendra Nurdin, Yanbei Chen, Xiang Li, Haixing Miao. 2021-10-15. Designing optimal linear detectors -- a bottom-up approach. https://arxiv.org/abs/2110.07942

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