Superconductivity in the vicinity of antiferromagnetic order in CrAs.
One of the common features of unconventional superconducting systems such as the heavy fermion, high transition temperature cuprate and iron pnictide superconductors is that the superconductivity emerges in the vicinity of long range antiferromagnetically ordered state. In addition to doping charge carriers, the application of external pressure is an effective and clean approach to induce unconventional superconductivity near a magnetic quantum critical point. Here we report on the discovery of superconductivity on the verge of antiferromagnetic order in CrAs via the application of external pressure. Bulk superconductivity with Tc2 K emerges at the critical pressure Pc8 kbar, where the first order antiferromagnetic transition at T(N)265 K under ambient pressure is completely suppressed. The close proximity of superconductivity to an antiferromagnetic order suggests an unconventional pairing mechanism for CrAs. The present finding opens a new avenue for searching novel superconductors in the Cr and other transition metal based systems.
Nature communications