The superconducting gap of in situ MgB2 thin films by microwave surface impedance measurements
نویسندگان
چکیده
Precision measurements of the microwave surface resistance Rs of in situ MgB2 films directly reveal an exponential behavior of Rs at low temperature indicating a fully-gapped order parameter. The entire temperature dependence of Rs is well described by a Mattis–Bardeen formalism, but with a small gap ratio of D(0)/kTc50.72, corresponding to D(0)51.9 meV. © 2002 American Institute of Physics. @DOI: 10.1063/1.1517181#
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