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arXiv · 2101.01504

Dynamic sensitivity of quantum Rabi model with quantum criticality

Ying Hu·Jian Huang·Jin-Feng Huang·Qiong-Tao Xie·Jie-Qiao Liao
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Abstract

We study the dynamic sensitivity of the quantum Rabi model, which exhibits quantum criticality in the finite-component-system case. This dynamic sensitivity can be detected by introducing an auxiliary two-level atom far-off-resonantly coupled to the cavity field of the quantum Rabi model. We find that when the quantum Rabi model goes through the critical point, the auxiliary atom experiences a sudden decoherence, which can be characterised by a sharp decay of the Loschmidt echo. Our scheme will provide a reliable way to observe quantum phase transition in ultrastrongly coupled quantum systems.

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Ying Hu, Jian Huang, Jin-Feng Huang, Qiong-Tao Xie, Jie-Qiao Liao. 2021-01-05. Dynamic sensitivity of quantum Rabi model with quantum criticality. https://arxiv.org/abs/2101.01504

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