Pressure effect on Charge-Density-Wave in Per2M(mnt)2 (M=Pt, Au)

The Charge-Density-Wave (CDW) transition temperature TCDW of quasione-dimensional conductors Per2M(mnt)2 (M=Au, Pt) steeply decreases with increasing pressure up to 0.5 GPa but the pressure-induced transition to a metallic state is not observed at least up to 1.5 GPa. At ambient pressure the resistance decreases with decreasing temperature but turns to increase at the temperature Tmin corresponding to the resistance minimum, and then it exponentially raises below TCDW. Tmin initially decreases steeply with increasing pressure but becomes nearly constant at pressures above 0.5 GPa, where TCDW disappears. Nonlinear conduction is observed under pressures above 1 GPa and at temperatures below 4.2 K. The present results are discussed in terms of the pressure-induced quantum melting of the CDW state.