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arXiv · 2106.02462

Conservation of chirality at a junction between two Weyl semimetals

Serguei Tchoumakov·Bogusz Bujnowski·Jonathan Noky·Johannes Gooth·Adolfo G. Grushin·Jérôme Cayssol
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Abstract

In Weyl semimetals the location of linear band crossings, the Weyl cones, is not bound to any high symmetry point of the Brillouin zone, unlike the Dirac nodes in graphene. This flexibility is advantageous for valleytronics, where information is encoded in the valleys of the band structure when intervalley scattering is weak. However, if numerous Weyl cones coexist the encoded information can decohere rapidly because of band mixing. Here, we investigate how the helical iso-spin texture of Weyl cones affects valleytronics in heterojunctions of Weyl materials, and show how the chirality of this iso-spin texture can serve to encode information.

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Serguei Tchoumakov, Bogusz Bujnowski, Jonathan Noky, Johannes Gooth, Adolfo G. Grushin, Jérôme Cayssol. 2021-06-04. Conservation of chirality at a junction between two Weyl semimetals. https://doi.org/10.1103/physrevb.104.125308

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