Currents and pseudomagnetic fields in strained graphene rings

TL;DR

This paper investigates how strain-induced pseudomagnetic fields affect electronic properties and persistent currents in graphene rings, revealing inhomogeneous current distributions and potential methods to probe pseudomagnetic field characteristics.

Contribution

It demonstrates the impact of strain on pseudomagnetic fields and persistent currents in graphene rings, highlighting the interplay between real and pseudo magnetic effects.

Findings

Strain induces sizable pseudomagnetic fields in graphene rings.

Deformations cause inhomogeneous persistent currents.

Pseudomagnetic fields can modulate local magnetic flux effects.

Abstract

We study the effects of strain on the electronic properties and persistent current characteristics of a graphene ring using the Dirac representation. For a slightly deformed graphene ring flake, one obtains sizable pseudomagnetic (gauge) fields that may effectively reduce or enhance locally the applied magnetic flux through the ring. Flux-induced persistent currents in a flat ring have full rotational symmetry throughout the structure; in contrast, we show that currents in the presence of a circularly symmetric deformation are strongly inhomogeneous, due to the underlying symmetries of graphene. This result illustrates the inherent competition between the `real' magnetic field and the `pseudo' field arising from strains, and suggest an alternative way to probe the strength and symmetries of pseudomagnetic fields on graphene systems.