Pressure-induced suppression of charge density wave and emergence of superconductivity in 1T-VSe2

Abstract

We report pressure evolution of charge density wave (CDW) order and the emergence of superconductivity (SC) in 1T−VSe2 single crystal by studying resistance and magnetoresistance behavior under high pressure. With increasing quasihydrostatic pressure the CDW order enhances with its ordering temperature (∼100K at ambient P) increasing marginally up to 5 GPa. At higher pressures, CDW-like resistance anomaly increases more rapidly with the characteristic temperature reaching ∼ 290K at 14.2 GPa. Upon further increase of pressure, the resistance anomaly due to CDW order gets suppressed drastically with rapidly increased metallicity (as clearly evidenced from the increased RRR value) and superconductivity emerges at ∼ 15 GPa, with the onset critical temperature (Tc) ∼4 K. The pressure dependence of Tc is found negligible, different from an increase or a dome-shaped behavior seen in isostructural layered diselenide superconductors. The high-pressure magnetoresistance and Hall measurements suggest successive electronic structural changes with Fermi surface modifications at 5 and ∼12 GPa.