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arXiv · 2305.06399

Quantization of the higher Berry curvature and the higher Thouless pump

Adam Artymowicz·Anton Kapustin·Nikita Sopenko
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Abstract

We show that for families of 1d lattice systems in an invertible phase, the cohomology class of the higher Berry curvature can be refined to an integral degree-3 class on the parameter space. Similarly, for families of U(1)-invariant 2d lattice systems in an invertible phase, the higher Thouless pump can be refined to an integral degree-2 class on the parameter space. We show that the 2d Thouless pump can be identified with an excess Berry curvature of a flux insertion.

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Adam Artymowicz, Anton Kapustin, Nikita Sopenko. 2023-05-10. Quantization of the higher Berry curvature and the higher Thouless pump. https://arxiv.org/abs/2305.06399

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