Novel Pressure Phase Diagram of Heavy Fermion Superconductor CePt$_{3}$Si Investigated by ac Calorimetry

TL;DR

This study maps the pressure-temperature phase diagram of CePt$_3$Si, revealing unique behaviors of its antiferromagnetic and superconducting phases under high pressure, using ac calorimetry.

Contribution

It provides the first detailed pressure phase diagram of CePt$_3$Si, highlighting its unusual coexistence and suppression of magnetic and superconducting states.

Findings

Néel temperature decreases to zero at ~0.6 GPa

Superconductivity persists up to ~1.5 GPa

Unique pressure phase diagram for heavy fermion superconductors

Abstract

The pressure dependences of the antiferromagnetic and superconducting transition temperatures have been investigated by ac heat capacity measurement under high pressures for the heavy-fermion superconductor CePt$_3$Si without inversion symmetry in the tetragonal structure. The N\'{e}el temperature $T_{\rm N}$ = 2.2 K decreases with increasing pressure and becomes zero at the critical pressure $P_{\rm AF}$ $\simeq$ 0.6 GPa. On the other hand, the superconducting phase exists in a wider pressure region from ambient pressure to about 1.5 GPa. The pressure phase diagram of CePt$_3$Si is thus very unique and has never been reported before for other heavy fermion superconductors.