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Evidence of Electromagnetic Absorption by Collective Modes in the Heavy Fermion Superconductor UBe13

J. R. Feller·C. -C. Tsai·J. B. Ketterson·J. L. Smith·Bimal K. Sarma
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Abstract

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.

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J. R. Feller, C. -C. Tsai, J. B. Ketterson, J. L. Smith, Bimal K. Sarma. 2001-04-23. Evidence of Electromagnetic Absorption by Collective Modes in the Heavy Fermion Superconductor UBe13. https://doi.org/10.1103/physrevlett.88.247005

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