Analytic solution to pseudo-Landau levels in strongly bent graphene nanoribbons

TL;DR

This paper provides an analytical solution for pseudo-Landau levels in strongly bent graphene nanoribbons, accounting for nonuniform Fermi velocity and pseudomagnetic fields, aiding experimental detection and applications in straintronics.

Contribution

It introduces a novel analytical approach to solve for pseudo-Landau levels under strong, nonuniform strain in graphene nanoribbons, considering complex space-dependent effects.

Findings

Analytic solutions are detectable via ARPES.

Quantitative comparison with transport experiments is possible.

The approach can be extended to other 2D and topological materials.

Abstract

Nonuniform elastic strain is known to induce pseudo-Landau levels in Dirac materials. But these pseudo-Landau levels are hardly resolvable in an analytic fashion when the strain is strong, because of the emerging complicated space dependence in both the strain-modulated Fermi velocity and the strain-induced pseudomagnetic field. We analytically characterize the solution to the pseudo-Landau levels in experimentally accessible strongly bent graphene nanoribbons, by treating the effects of the nonuniform Fermi velocity and pseudomagnetic field on equal footing. The analytic solution is detectable through the angle-resolved photoemission spectroscopy (ARPES) and allows quantitative comparison between theories and various transport experiments, such as the Shubnikov-de Haas oscillation in the complete absence of magnetic fields and the negative strain-resistivity resulting from the valley anomaly. The analytic solution can be generalized to twisted two-dimensional materials and topological materials and will shed a new light on the related experimental explorations and straintronics applications.