Pressure-Induced Heavy-Fermion Superconductivity in Antiferromagnet CeIrSi₃without Inversion Symmetry

We report the discovery of pressure-induced superconductivity in an antiferromagnet CeIrSi 3 , 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.