Fingerprints of a position-dependent Fermi velocity on scanning tunnelling spectra of strained graphene

• Main Authors: Oliva-Leyva, M, Barrios-Vargas, J. E, Wang, Chumin
• Format: Journal Article
• Language: English
• Published: 23-01-2018
• Subjects: Physics - Mesoscale and Nanoscale Physics
• DOI: 10.48550/arxiv.1801.07617

J. Phys.: Condens. Matter 30 085702 (2018) Nonuniform strain in graphene induces a position dependence of the Fermi
velocity, as recently demonstrated by scanning tunnelling spectroscopy
experiments. In this work, we study the effects of a position-dependent Fermi
velocity on the local density of states (LDOS) of strained graphene, without
and with the presence of a uniform magnetic field. The variation of LDOS
obtained from tight-binding calculations is successfully explained by
analytical expressions derived within the Dirac approach. These expressions
also rectify a rough Fermi velocity substitution used in the literature that
neglects the strain-induced anisotropy. The reported analytical results could
be useful for understanding the nonuniform strain effects on scanning
tunnelling spectra of graphene, as well as when it is exposed to an external
magnetic field.