Subsurface bending and reorientation of tilted vortex lattices in bulk isotropic superconductors due to Coulomb-like repulsion at the surface

Abstract

We study vortex lattices (VLs) in superconducting weak-pinning platelet-like single crystals of β-Bi2Pd in tilted magnetic fields with a scanning tunneling microscope. We show that vortices exit the sample perpendicular to the surface and are thus bent beneath the surface. The structure and orientation of the tilted VLs in the bulk are, for large tilt angles, strongly affected by Coulomb-type intervortex repulsion at the surface due to stray magnetic fields.