Quasiparticles in the vortex lattice of unconventional superconductors: Bloch waves or Landau levels?

TL;DR

This paper introduces a new gauge transformation for quasiparticles in unconventional superconductors, revealing that their low-energy states form Bloch waves in a vortex lattice, offering deeper physical insights.

Contribution

It develops a novel singular gauge transformation that allows a comprehensive solution, showing that quasiparticles form Bloch waves rather than Landau levels in a periodic vortex lattice.

Findings

Quasiparticle states are Bloch waves in a vortex lattice.

The new gauge transformation simplifies understanding spectral properties.

Provides a full solution at low and intermediate fields.

Abstract

A novel singular gauge transformation is developed for quasiparticles in the mixed state of a strongly type-II superconductor which permits a full solution of the problem at low and intermediate fields. For a periodic vortex lattice the natural low-energy quasiparticle states are Bloch waves rather than Landau levels discussed in the recent literature. The new representation elucidates the physics considerably and provides fresh insights into the spectral properties of such systems.