Superconductivity in Strong Spin Orbital Coupling Compound Sb(2)Se(3)

Recently, A(2)B(3) type strong spin orbital coupling compounds such as Bi(2)Te(3), Bi(2)Se(3) and Sb(2)Te(3) were theoretically predicated to be topological insulators and demonstrated through experimental efforts. The counterpart compound Sb(2)Se(3) on the other hand was found to be topological trivial, but further theoretical studies indicated that the pressure might induce Sb(2)Se(3) into a topological nontrivial state. Here, we report on the discovery of superconductivity in Sb(2)Se(3) single crystal induced via pressure. Our experiments indicated that Sb(2)Se(3) became superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition at ~3 GPa which should be related to the topological quantum transition. The superconducting transition temperature (T(C)) increased to around 8.0 K with pressure up to 40 GPa while it keeps ambient structure. High pressure Raman revealed that new modes appeared around 10 GPa and 20 GPa, respectively, which correspond to occurrence of superconductivity and to the change of T(C) slop as the function of high pressure in conjunction with the evolutions of structural parameters at high pressures.