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arXiv · 2308.02130

Spin-valley locking in Kekulé-distorted graphene with Dirac-Rashba interactions

David A. Ruiz-Tijerina·Jesús Arturo Sánchez-Sánchez·Ramon Carrillo-Bastos·Santiago Galván y García·Francisco Mireles
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Abstract

The joint effects of Kekulé lattice distortions and Rashba-type spin-orbit coupling on the electronic properties of graphene are explored. We modeled the position dependence of the Rashba energy term in a manner that allows its seamless integration into the scheme introduced by Gamayun et al.[New J. Phys. 20, 023016 (2018)] to describe graphene with Kekulé lattice distortion. Particularly for the Kekulé-Y texture, the effective low energy Dirac Hamiltonian contains a new spin-valley locking term, in addition to the well-known Rashba-induced momentum-pseudospin and spin-pseudospin couplings, and the Kekulé-induced momentum-valley coupling term. We report on the low-energy band structure and Landau level spectra of Rashba-spin-orbit-coupled Kek-Y graphene, and propose an experimental scheme to discern between the presence of Rashba spin-orbit coupling, Kek-Y lattice distortion, and both, based on doping-dependent magnetotransport measurements.

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David A. Ruiz-Tijerina, Jesús Arturo Sánchez-Sánchez, Ramon Carrillo-Bastos, Santiago Galván y García, Francisco Mireles. 2023-08-04. Spin-valley locking in Kekulé-distorted graphene with Dirac-Rashba interactions. https://arxiv.org/abs/2308.02130

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