Anisotropy of heat capacity in Pauli limited unconventional superconductors

TL;DR

This paper investigates how the heat capacity anisotropy in unconventional superconductors, influenced by magnetic fields, persists despite strong paramagnetic effects, providing insights into nodal structures.

Contribution

It demonstrates that heat capacity anisotropy remains observable in Pauli limited superconductors, extending previous understanding to systems with strong spin coupling.

Findings

Heat capacity anisotropy persists with strong paramagnetic coupling.

Magnetic field angle dependence reveals nodal positions.

Provides a method to probe nodal structures in unconventional superconductors.

Abstract

Diamagnetically coupled magnetic field can be used as a probe of nodal positions in unconventional superconductors. The heat capacity depends on the angle $\phi_0$ between the magnetic field and the nodal directions. We show that the anisotropy $C(\phi_0)$ persists even in systems with strong paramagnetic coupling to the electrons's spins.