Superconducting and thermoelectric properties of new layered superconductor Bi4O4S3

Polycrystalline sample of the new layered superconductor Bi4O4S3 is successfully synthesized by solid-state reaction method by using Bi, S and Bi2O3 powders with one-step solid state reaction. The superconducting transition temperature (Tconset=4.5K), the zero resistance transition temperature (Tc0 = 4.07 K) and the diamagnetic transition temperature (4.02 K at H = 10 Oe) were confirmed by electrical transport and magnetic measurements. Also, our results indicate a typical type II-superconductor behavior and the charge carriers are mainly electron-type. In addition, a large thermoelectric effect was observed with a dimensionless thermoelectric figure of merit (ZT) of about 0.03 at 300 K.