Bean-Livingston barrier enhancement on nodal surface of the d-wave superconductor YBa2Cu3O{7-x}

TL;DR

This study investigates how surface currents in YBa2Cu3O7-x superconducting films increase the magnetic field required for vortex entry, confirming theoretical predictions of enhanced Bean-Livingston barriers on nodal surfaces.

Contribution

It provides experimental evidence of increased vortex entry barriers on the nodal surface of a d-wave superconductor, aligning with recent theoretical models.

Findings

Vortex entry field exceeds that of conventional superconductors

Surface currents shift Andreev-Saint-James bound states energy

Enhanced Bean-Livingston barrier observed at low temperatures

Abstract

Vortex entry into (110) oriented YBa$_2$Cu$_3$O$_{7-x}$ films has been studied by tunneling into Andreev - Saint-James bound states, whose energy is shifted by surface currents. At low temperatures, the characteristic field for vortex entry has been found to increase up to values several times higher than that of the Bean-Livingston entry field for conventional superconductors, in agreement with recent theoretical predictions.