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arXiv · 1707.02465

Strain-controlled valley and spin separation in silicene heterojunctions

Yuan Li·H. B. Zhu·G. Q. Wang·Y. Z. Peng·J. R. Xu·Z. H. Qian·R. Bai·G. H. Zhou·C. Yesilyurt·Z. B. Siu·M. B. A. Jalil
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Abstract

We adopt the tight-binding mode-matching method to study the strain effect on silicene heterojunctions. It is found that valley- and spin-dependent separation of electrons cannot be achieved by the electric field only. When a strain and an electric field are simultaneously applied to the central scattering region, not only are the electrons of valleys K and K' separated into two distinct transmission lobes in opposite transverse directions, but the up-spin and down-spin electrons will also move in the two opposite transverse directions. Therefore, one can realize an effective modulation of valley- and spin-dependent transport by changing the amplitude and the stretch direction of the strain. The phenomenon of the strain-induced valley and spin deflection can be exploited for silicene-based valleytronics devices.

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Yuan Li, H. B. Zhu, G. Q. Wang, Y. Z. Peng, J. R. Xu, Z. H. Qian, R. Bai, G. H. Zhou, C. Yesilyurt, Z. B. Siu, M. B. A. Jalil. 2018-06-28. Strain-controlled valley and spin separation in silicene heterojunctions. https://doi.org/10.1103/physrevb.97.085427

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