A study on the electrical property of HgSe under high pressure

Using a microcircuit fabricated on a diamond anvil cell, we have measuredin-situ conductivity of HgSe under high pressures, and investigated thetemperature dependence of conductivity under several different pressures. The resultshows that HgSe has a pressure-induced transition sequence from a semimetalto a semiconductor to a metal, similar to that in HgTe. Severaldiscontinuous changes in conductivity are observed at around 1.5, 17, 29and 49GPa, corresponding to the phase transitions from zinc-blende tocinnabar to rocksalt to orthorhombic to an unknown structure, respectively.In comparison with HgTe, it is speculated that the unknown structure may bea distorted CsCl structure. For the cinnabar-HgSe, the energy gap as afunction of pressure is obtained according to the temperature dependence ofconductivity. The plot of the temperature dependence of conductivityindicates that the unknown structure of HgSe has an electrical property of aconductor.