Gapless Fermi Surfaces in anisotropic multiband superconductors in magnetic field

Abstract

We propose that a new state with a fully gapless Fermi surface appears in quasi-2D multiband superconductors in magnetic field applied parallel to the plane. It is characterized by a paramagnetic moment caused by a finite density of states on the open Fermi surface. We calculate thermodynamic and magnetic properties of the gapless state for both s-wave and d-wave cases, and discuss the details of the 1-st order metamagnetic phase transition that accompanies the appearance of the new phase in s-wave superconductors. We suggest possible experiments to detect this state both in the s-wave (2-H NbSe2) and d-wave (CeCoIn5) superconductors.

4 pages, 2 figures

References in corpus (4)

• Ginzburg-Landau theory of vortices in a multi-gap superconductor
• Phase Diagram and Spectroscopy of FFLO states of two-dimensional d-wave superconductors
• Observation of Spin Susceptibility Enhancement in the Possible FFLO State in CeCoIn${}_5$
• Breached Superfluidity via P-Wave Coupling

Cited by in corpus (5)

• Experimental evidence for a two-gap structure of superconducting NbSe_2: a specific heat study in external magnetic fields
• Primary role of the barely occupied states in the charge density wave formation of NbSe2
• Evolution of the superconducting energy gap structure concomitant with Fermi surface reconstruction in the heavy-fermion superconductor CeCoIn5
• Magnetic field-induced gapless state in multiband superconductors
• Field-induced gapless electron pocket in the superconducting vortex phase of YNi2B2C as probed by magnetoacoustic quantum oscillations