Heat conduction in the borocarbide superconductor LuNi2B2C

Abstract The thermal conductivity of the borocarbide superconductor LuNi 2 B 2 C (T c = 16K) was measured in the temperature range from 50 mK to 100 K. An unusually large phonon peak is observed in the superconducting state and the data at very low temperature is consistent with this material being an s -wave superconductor.