Quantum oscillations without magnetic field

TL;DR

This paper predicts that in Dirac and Weyl semimetals, quantum oscillations can occur without magnetic fields, driven instead by elastic strain acting as a pseudomagnetic field, leading to observable oscillations in electronic properties.

Contribution

It introduces the novel concept that elastic strain can induce quantum oscillations in Dirac and Weyl semimetals without magnetic fields, expanding understanding of quantum phenomena in these materials.

Findings

Strain acts as a chiral gauge potential in Dirac/Weyl semimetals.

Strain-induced pseudomagnetic fields can reach up to 15T.

Quantum oscillations occur in the absence of magnetic fields, periodic in inverse pseudomagnetic field.

Abstract

When magnetic field $B$ is applied to a metal, nearly all observable quantities exhibit oscillations periodic in $1/B$. Such quantum oscillations reflect the fundamental reorganization of electron states into Landau levels as a canonical response of the metal to the applied magnetic field. We predict here that, remarkably, in the recently discovered Dirac and Weyl semimetals quantum oscillations can occur in the complete absence of magnetic field. These zero-field quantum oscillations are driven by elastic strain which, in the space of the low-energy Dirac fermions, acts as a chiral gauge potential. We propose an experimental setup in which the strain in a thin film (or nanowire) can generate pseudomagnetic field $b$ as large as 15T and demonstrate the resulting de Haas-van Alphen and Shubnikov-de Haas oscillations periodic in $1/b$.