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arXiv · 1501.00114

Perfect Valley Filter in Topological Domain Wall

Hui Pan·Xin Li·Fan Zhang·Shengyuan A. Yang
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Abstract

We propose a realization of perfect valley filters based on the chiral domain-wall channels between a quantum anomalous Hall insulator and a quantum valley Hall insulator. Uniquely, all these channels reside in the same valley and propagate unidirectionally, $100\%$ valley-polarizing passing-by carriers without backscattering. The valley index, the chirality, and the number of the channels are protected by topological charges, controllable by external fields, and detectable by circular dichroism.

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Hui Pan, Xin Li, Fan Zhang, Shengyuan A. Yang. 2014-12-31. Perfect Valley Filter in Topological Domain Wall. https://doi.org/10.1103/physrevb.92.041404

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