Superconductivity in a New Layered BiSe₂-Based Compound LaO_1-xBiSe₂

We report in this contribution a new superconductor LaO_1-xBiSe₂ which was synthesized by solid-state reaction method. The structure analysis indicated that LaO_1-xBiSe₂ compound has typical CeOBiS₂-type structure with P4/nmm space group. Compared with the parent phase LaOBiSe₂, the lattice parameters of LaO_0.9BiSe₂ contracted. Physical property characterizations demonstrated that the charge density wave behavior of the parent phase was suppressed by oxygen vacancies and a superconducting transition at 2.9 K was observed in LaO_0.9BiSe₂ sample. The present work shows that the introduction of oxygen vacancies without extrinsic doping is an effective approach to induce superconductivity in the LaOBiSe₂ system.