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arXiv · 2212.10760

Critical quantum sensing based on the Jaynes-Cummings model with a squeezing drive

Abstract

Quantum sensing improves the accuracy of measurements of relevant parameters by exploiting the unique properties of quantum systems. The divergent susceptibility of physical systems near a critical point for quantum phase transition enables criticality-enhanced quantum sensing. The quantum Rabi model (QRM), composed of a single qubit coupled to a single bosonic field, represents a good candidate for realizing such critical enhancement for its simplicity, but it is experimentally challenging to achieve the ultrastrong qubit-field coupling required to realize the critical phenomena. In this work, we explore an alternative to construct the analog of the QRM for the sensing, exploiting the criticality appearing in the Jaynes-Cummings (JC) model whose bosonic field is parametrically driven, not necessitating the ultrastrong coupling condition thus to some extent relaxing the requirement for the practical implementation.

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Jia-Hao Lü, Wen Ning, Xin Zhu, Fan Wu, Li-Tuo Shen, Zhen-Biao Yang, Shi-Biao Zheng. 2022-12-21. Critical quantum sensing based on the Jaynes-Cummings model with a squeezing drive. https://doi.org/10.1103/physreva.106.062616

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