Quantum oscillations and Dirac-Landau levels in Weyl superconductors

TL;DR

This paper predicts that elastic strain in Weyl superconductors can induce chiral pseudo-magnetic fields, leading to Dirac-Landau levels and observable quantum oscillations in quasiparticle properties, offering new experimental insights.

Contribution

It introduces the concept that strain can generate pseudo-magnetic fields in Weyl superconductors, enabling quantum oscillations despite superconductivity.

Findings

Strain induces chiral pseudo-magnetic fields in Weyl superconductors.

Pseudo-magnetic fields create Dirac-Landau levels at low energy.

Quantum oscillations can be observed via thermal conductivity measurements.

Abstract

When magnetic field is applied to metals and semimetals quantum oscillations appear as individual Landau levels cross the Fermi level. Quantum oscillations generally do not occur in superconductors (SC) because magnetic field is either expelled from the sample interior or, if strong enough, drives the material into the normal state. In addition, elementary excitations of a superconductor -- Bogoliubov quasiparticles -- do not carry a well defined electric charge and therefore do not couple in a simple way to the applied magnetic field. We predict here that in Weyl superconductors certain types of elastic strain have the ability to induce chiral pseudo-magnetic field which can reorganize the electronic states into Dirac-Landau levels with linear band crossings at low energy. The resulting quantum oscillations in the quasiparticle density of states and thermal conductivity can be experimentally observed under a bending deformation of a thin film Weyl SC and provide new insights into this fascinating family of materials.