Pseudo-Landau levels of Bogoliubov quasiparticles in strained nodal superconductors

TL;DR

This paper explores how strain or pairing variations in nodal superconductors can create pseudo-Landau levels for Bogoliubov quasiparticles, revealing new ways to manipulate quasiparticle states.

Contribution

It extends the concept of strain-induced pseudo-Landau levels from Dirac fermions to Bogoliubov quasiparticles in nodal superconductors, combining theoretical and numerical analysis.

Findings

Spatial variations can induce pseudo-magnetic fields for QPs

Pseudo-Landau levels can be realized in cuprates via strain or proximity effects

Signatures are detectable in tunneling experiments

Abstract

Motivated by theory and experiments on strain induced pseudo-Landau levels (LLs) of Dirac fermions in graphene and topological materials, we consider its extension for Bogoliubov quasiparticles (QPs) in a nodal superconductor (SC). We show, using an effective low energy description and numerical lattice calculations for a d-wave SC, that a spatial variation of the electronic hopping amplitude or a spatially varying s-wave pairing component can act as a pseudo-magnetic field for the Bogoliubov QPs, leading to the formation of pseudo-LLs. We propose realizations of this phenomenon in the cuprate SCs, via strain engineering in films or nanowires, or s-wave proximity coupling in the vicinity of a nematic instability, and discuss its signatures in tunneling experiments.