Pressure-induced superconductivity in MoP

Topological semimetal, a novel state of quantum matter hosting exotic emergent quantum phenomena dictated by the nontrivial band topology, has emerged as a new frontier in condensed-matter physics. Very recently, the coexistence of triply degenerate points of band crossing and Weyl points near the Fermi level was theoretically predicted and experimentally identified in MoP. Via high-pressure electrical transport measurements, we report here the emergence of pressure-induced superconductivity in MoP with a critical transition temperature T-c of ca. 2.5 K at ca. 30 GPa. No structural phase transition is observed up to ca. 60 GPa via synchrotron X-ray diffraction study. Accordingly, the topologically nontrivial band protected by the crystal structure symmetries and superconductivity are expected to coexist at pressures above 30 GPa, consistent with density functional theory calculations. Thus, the pressurized MoP represents a promising candidate of topological superconductor. Our finding is expected to stimulate further exploitation of exotic emergent quantum phenomena in novel unconventional fermion system.