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arXiv · 2304.00187

Geometric phases of Topological Systems under Quench Process

Zhan Gao·Yan He
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Abstract

We study the time evolution of geometric phases of one dimensional topological models under the quench dynamics. Taking the Creutz ladder model as an example, it is found that the Berry phase is fixed as the parameter is suddenly tuned across the topological phase boundary, given that the chiral symmetry of the model is preserved. At finite temperature, the Uhlmann phase displays abrupt jumps between the two quantized values, which indicates the topological transition at certain times after the quench. Both the Berry and Uhlmann phase will deviate from quantized values if the chiral symmetry of the model is broken. The relation between the Uhlmann phase and Loshmidt rate function under the quench process is also discussed.

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Zhan Gao, Yan He. 2023-04-01. Geometric phases of Topological Systems under Quench Process. https://doi.org/10.1103/physrevb.108.085126

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