Pressure-Induced Heavy-Fermion Superconductivity in Antiferromagnet CeIrSi₃ without Inversion Symmetry

Abstract

We report the discovery of pressure-induced superconductivity in an antiferromagnet CeIrSi₃, which lacks inversion symmetry in the tetragonal crystal structure. The Néel temperature T_N=5.0 K at ambient pressure decreases monotonically with increasing pressure, and becomes zero at about 2.5 GPa. Superconductivity appears in a wide pressure region from 1.8 GPa to about 3.5 GPa, with a relatively large superconduting transition temperature T_sc=1.6 K and a large upper critical field H_c2(0)=11.1 T at 2.5 GPa, indicating heavy-fermion superconductivity.