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arXiv · 1705.07067

Electrically tunable valley polarization in Weyl semimetals with tilted energy dispersion

Can Yesilyurt·Zhuo Bin Siu·Seng Ghee Tan·Gengchiau Liang·Shengyuan A. Yang·Mansoor B. A. Jalil
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Abstract

Tunneling transport across the p-n-p junction of Weyl semimetal with tilted energy dispersion is investigated. We report that the electrons around different valleys experience opposite direction refractions at the barrier interface when the energy dispersion is tilted along one of the transverse directions. Chirality dependent refractions at the barrier interface polarize the Weyl fermions in angle-space according to their valley index. A real magnetic barrier configuration is used to select allowed transmission angles, which results in electrically controllable and switchable valley polarization. Our findings may pave the way for experimental investigation of valley polarization, as well as valleytronic and electron optic applications in Weyl semimetals.

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Can Yesilyurt, Zhuo Bin Siu, Seng Ghee Tan, Gengchiau Liang, Shengyuan A. Yang, Mansoor B. A. Jalil. 2017-05-19. Electrically tunable valley polarization in Weyl semimetals with tilted energy dispersion. https://doi.org/10.1038/s41598-019-40947-2

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