High-pressure effects on superconducting properties and crystal structure of Bi-based layered superconductor La2O2Bi3Ag0.6Sn0.4S6

The effects of pressure on the superconducting properties of a Bi-based layered superconductor La2O2Bi3Ag0.6Sn0.4S6, which possesses a four-layer-type conducting layer, have been studied through the electrical resistance and magnetic susceptibility measurements. The crystal structure under pressure was examined using synchrotron x-ray diffraction at SPring-8. In the low-pressure regime, bulk superconductivity with a transition temperature T-c of similar to 4.5 K was induced by pressure, which was achieved by in-plane chemical pressure effect owing to the compression of the tetragonal structure. In the high-pressure regime above 6.4 GPa, a structural symmetry lowering was observed, and superconducting transitions with a T-c similar to 8 K were observed. Our results suggest the possible commonality on the factor essential for T-c in Bi-based superconductors with two-layer-type and four-layer-type conducting layers.

Automated summary

The study investigated the effects of pressure on the superconducting properties of a Bi-based layered superconductor La2O2Bi3Ag0.6Sn0.4S6 through electrical resistance and magnetic susceptibility measurements. The results showed that pressure induced bulk superconductivity at low pressure and structural symmetry lowering at high pressure, leading to higher superconducting transition temperatures.