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arXiv · 2409.12738

Qubit coupled with an effective negative-absolute-temperature bath in off-resonant collision model

Wei-Bin Yan·Zhong-Xiao Man·Ying-Jie Zhang·Yun-Jie Xia
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Abstract

Quantum collision model provides a promising tool for investigating system-bath dynamics. Most of the studies on quantum collision models work in the resonant regime. In quantum dynamics, the off-resonant interaction often brings in exciting ffects. It is thereby attractive to investigate quantum collision models in the off-resonant regime. On the other hand, a bath with a negative absolute temperature is anticipated to be instrumental in developing thermal devices. The design of an effective bath with negative absolute temperature coupled to a qubit is significant for developing such thermal devices. We establish an effective negative-absolute-temperature bath coupled to a qubit with a quantum collision model in a far-off-resonant regime. We conduct a detailed and systematic investigation on the off-resonant collision model. There is an additional constraint on the collision duration resulting from the far-off resonant collision. The dynamics of the collision model in the far-off-resonant regime are different from the one beyond the far-off-resonant regime. Numerical simulations confirm the validity of the proposed approach.

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Wei-Bin Yan, Zhong-Xiao Man, Ying-Jie Zhang, Yun-Jie Xia. 2024-09-19. Qubit coupled with an effective negative-absolute-temperature bath in off-resonant collision model. https://arxiv.org/abs/2409.12738

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