Detection of high-field superconducting phase in CeCoIn$_5$ with magnetic susceptibility

TL;DR

This study investigates a high-field superconducting phase in CeCoIn5 using ac susceptibility measurements, revealing a phase transition and pressure effects on the critical field and phase stability.

Contribution

It provides new experimental evidence for a high-field phase transition in CeCoIn5 and explores how uniaxial pressure influences this phase and the critical magnetic field.

Findings

Evidence for a high-field phase transition within the superconducting state.

Uniaxial pressure affects the critical field Hc2 and the high-field phase.

Behavior of Hc2 under pressure varies with field orientation.

Abstract

We measure the ac susceptibility of single-crystal CeCoIn5 in dc field parallel to the c axis and find further evidence for a high-field phase transition within the superconducting phase in this orientation. We apply up to 2.3 kbar uniaxial pressure along the c axis and discuss the pressure dependence of the high-field phase. We also report the behavior of Hc2 under uniaxial pressure for field along c.