Superconducting Transition Temperature ofLa3S4

Abstract

The superconducting transition temperature of stoichiometric ${\mathrm{La}}_3$ ${\mathrm{S}}_4$ has been measured by two different methods and has been found to be (8.25±0.2)°K. A range of superconducting compositions exists in the metal-rich end of the $\gamma$ phase of lanthanum sulfide. Part of the sulfur-rich end of the $\gamma$ phase is nonsuperconducting. The superconducting transition temperature of $\gamma$-phase lanthanum sulfide appears to increase with increasing lanthanum content.