Evidence of Electromagnetic Absorption by Collective Modes in the Heavy Fermion Superconductor UBe13
We present results of a microwave surface impedance study of the heavy fermion superconductor UBe13. We clearly observe an absorption peak whose frequency- and temperature-dependence scales with the BCS gap function. Resonant absorption into a collective mode, with energy approximately proportional to the superconducting gap, is proposed as a possible explantation.
cond-mat.supr-con↗