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

The joint effects of Kekul\'e 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 Kekul\'e lattice distortion. Particularly for the Kekul\'e-Y (Kek-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 Kekul\'e-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.