Superconductivity in electron-doped PbBi2Te4

Single crystals of In-doped PbBi2Te4 are synthesized via a conventional solid-state method. Chemical analysis and Hall measurements indicate that In replaces Pb, introducing n-type carriers, creating Pb1-xInxBi2Te4. A superconducting transition is observed with a maximum transition temperature around 2.06 K for Pb1-xInxBi2Te4. Field-dependent transport measurements reveal type-II superconductivity and yield a maximum upper critical field around 1.55 T. Thermodynamic data indicates bulk superconductivity in the BCS weak-coupling limit. Our findings establish an ambient-pressure superconducting system in the AM2X4 family, and doped PbBi2Te4 as a promising platform for the study of topological superconductivity.