Electronic structure of a vortex line in a type-II superconductor: Effect of atomic crystal fields

Abstract
We consider a single vortex line in a tight-binding model on a square lattice with an s-wave pairing interaction. The model is exactly solved within the framework of the self-consistent Bogoliubov–de Gennes formalism for a finite-size system. The energy spectrum, quasiparticle amplitudes, the gap function, and the current distribution are calculated. The tunneling conductance images are found to show a fourfold star shape, whose orientation depends on the bias voltage.