| Abstract: | We report bulk superconductivity at 2.5 K in LaO0.5F0.5BiSe2 compound through the DC magnetic susceptibility and electrical resistivity measurements. The synthesized LaO0.5F0.5BiSe2 compound is crystallized in tetragonal structure with space group P4/nmm and Reitveld refined lattice parameters are a = 4.15(1) Å and c = 14.02(2) Å. The lower critical field of H c1 = 40 Oe, at temperature 2 K is estimated through the low field magnetization measurements. The LaO0.5F0.5BiSe2 compound showed metallic normal state electrical resistivity with residual resistivity value of 1.35 m Ω cm. The compound is a type-II superconductor, and the estimated H c2(0) value obtained by WHH formula is above 20 kOe for 90 % ρ n criteria. The superconducting transition temperature decreases with applied pressure till around 1.68 GPa and with further higher pressures a high- T c phase emerges with possible onset T c of above 5 K for 2.5 GPa. |
