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arXiv · 1905.12810

Multi-flavor Dirac fermions in Kekulé-distorted graphene bilayers

David A. Ruiz-Tijerina·Elias Andrade·Ramon Carrillo-Bastos·Francisco Mireles·Gerardo G. Naumis
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Abstract

Graphene's electronic structure can be fundamentally altered when a substrate- or adatom-induced Kekulé superlattice couples the valley and isospin degrees of freedom. Here, we show that the band structure of Kekulé-textured graphene can be re-engineered through layer stacking. We predict a family of Kekulé graphene bilayers that exhibit band structures with up to six valleys, and room-temperature Dirac quasiparticles whose masses can be tuned electrostatically. Fermi velocities half as large as in pristine graphene put this system in the strongly coupled regime, where correlated ground states can be expected.

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David A. Ruiz-Tijerina, Elias Andrade, Ramon Carrillo-Bastos, Francisco Mireles, Gerardo G. Naumis. 2019-05-30. Multi-flavor Dirac fermions in Kekulé-distorted graphene bilayers. https://doi.org/10.1103/physrevb.100.075431

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