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arXiv · 1312.0467

A Topological Spin Chern Pump

C. Q. Zhou·Y. F. Zhang·L. Sheng·R. Shen·D. N. Sheng·D. Y. Xing
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Abstract

We propose a one-dimensional electron model with parameters modulated adiabatically in closed cycles, which can continuously pump spin to leads. By defining the spin-polarized Wannier functions, we show that the spin pump is protected by the spin Chern numbers, so that it is stable to perturbations violating the time-reversal symmetry and spin conservation. Our work demonstrates the possibility and principle to realize topological spin pumps independent of any symmetries, and also suggests a possible way to experimentally observe the bulk topological invariants.

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C. Q. Zhou, Y. F. Zhang, L. Sheng, R. Shen, D. N. Sheng, D. Y. Xing. 2013-12-02. A Topological Spin Chern Pump. https://doi.org/10.1103/physrevb.90.085133

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