Superconductivity above 12 K with possible multiband features in CsCl-type PbS
He Zhang, Wei Zhong, Yanghao Meng, Binbin Yue, Xiaohui Yu, Jian-Tao Wang, Fang Hong
Abstract
Binary metal sulfides are a large material family with distinct physical behavior. Here, we report the superconductivity observed in PbS by means of pressure engineering. PbS undergoes a series of electronic phase transitions upon compression, and superconductivity occurs above 23.9 GPa in the high-pressure CsCl-type cubic phase. Further compression suppresses the superconductivity while the ${T}_{c}$ is reduced from $\ensuremath{\sim}12.0$ K at 23.9 GPa to 6.8 K at 44.3 GPa. Marginally higher ${T}_{c}\ensuremath{\approx}12.3$ K is observed at 19.1 GPa during pressure release. The magnetic field effect verifies the superconductivity with possible multiband features. It is noted that PbS is one of the few binary metal sulfide superconductors with a ${T}_{c}$ above 10 K. This work demonstrates that PbS has a high ${T}_{c}$ under a moderate pressure due to the chemical ``precompression'' effect, which is very close to the ${T}_{c}$ in pure sulfur at $\ensuremath{\sim}100$ GPa. PbS also shows unexpected multiband behavior in the cubic structure, benefiting the study of pressure-induced superconductivity and the underlying mechanism in metal sulfide compounds.