Luttinger liquid physics in the superconductor vortex core - art. no. 014506

We study several aspects of the structure of vortices in conventional s-wav e type-II superconductors. It is well known that there are low-energy quasi particles bound to the core of a vortex. We show that under certain conditi ons, these quasiparticles form a degenerate Fermi gas with a finite density of states at the Fermi energy. In three-dimensional superconductors. the r esult is a one-dimensional Fermi gas of quasiparticles bound to the core of a vortex line. As is usual in one-dimensional systems, interactions betwee n the quasiparticles lead to Luttinger liquid behavior. This may be probed through scanning tunneling microscopy into the vortex core. We further sugg est that a Peierls-type instability in the shape of the vortex line may dev elop due to interactions between the quasiparticle gas and fluctuations in the vortex line shape.