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arXiv · 2107.05560

Geometric pumping and dephasing at topological phase transition

B. Q. Song·J. D. H. Smith·L. Luo·J. Wang
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Abstract

A measure-preserving formalism (MPF) is constructed and applied to spin/band models, which yield observations about pumping. It occurs at topological phase transition (TPT), i.e., a $Z_2$-flip, suggesting that $Z_2$ can imply bulk effects. The model's asymptotic behavior is analytically solved via MPF. The pumping probability is geometric, fractional, and has a ceiling of $\frac{1}{2}$. Intriguingly, theorems are proved about occurrence conditions, which are linked to the system's dimension and the distinction between rational and irrational numbers. Experimental detection is discussed.

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B. Q. Song, J. D. H. Smith, L. Luo, J. Wang. 2021-07-12. Geometric pumping and dephasing at topological phase transition. https://doi.org/10.1103/physrevb.105.035101

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