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arXiv · 2212.13093

Dissipative Landau-Zener transition with decoherence rate

Le Tuan Anh Ho·Liviu Ungur·Liviu F. Chibotaru
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Abstract

An innovative microscopic model with a minimal number of parameters: tunneling splitting gap, external field sweeping velocity, and decoherence rate is used to describe dynamics of the dissipative Landau-Zener transition in the presence of the decoherence. In limiting cases, the derived equation of motion gives rise to the well-known Landau-Zener and Kayanuma formula. In a general case, the description demonstrates a non-monotonic flipping probability with respect to the sweeping velocity, which is also found in some other models. This non-monotony can be explained by considering the competition and timescale of the quantum tunneling, crossing period, and decoherence process. The simplicity and robustness of the theory offer a practical and novel description of the Landau-Zener transition. In addition, it promises an alternative method to the electron paramagnetic resonance in measuring the effective decoherence rate of relevant quantum systems.

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Le Tuan Anh Ho, Liviu Ungur, Liviu F. Chibotaru. 2022-12-26. Dissipative Landau-Zener transition with decoherence rate. https://arxiv.org/abs/2212.13093

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