高压下WSe_2的电学性质及金属化相变

Electrical Properties and Metallization of WSe_2 under High Pressure

利用高压原位电阻率测量技术,观察0～48.2 GPa内WSe2电阻率随压强的变化规律,并测量了WSe2电阻率在不同压强下随温度的变化关系.结果表明:WSe2电阻率在压力作用下的变化规律与杂质能级压致离化后的传导有关;由于压致能隙闭合,WSe2在38.1 GPa时发生等结构的半导体性到金属性的相转变.

The pressure dependence of electrical resistivity of WSe2 was observed by means of in situ high pressure electrical resistivity measurement in a range of 0—48.2 GPa.The temperature dependence of the electrical resistivity of WSe2 was measured under different pressures.The results show that the pressure response of the electrical resistivity of WSe2 was associated with the conduction of pressure-induced ionization of impurity levels;owing to the pressure induced band gap closure,WSe2 sample underwent an isostructural semiconductor-metal phase transition at 38.1 GPa.