Measurements of the temperature dependence of the surface resistance at 3GHz of 100μm-sized fragments of MgB2 separated powder were presented. The microwave surface resistance data were compared to experimental results for Nb, Bi2Sr2CaCu2O8+δ and theoretical predictions of s-wave weak coupling electron-phonon theory.

Microwave Surface Resistance in MgB2. A.A.Zhukov, L.F.Cohen, K.Yates, G.K.Perkins, Y.Bugoslavsky, M.Polichetti, A.Berenov, J.L.M.Driscoll, A.D.Caplin, L.Hao, J.Gallop: Superconductor Science and Technology, 2001, 14, L13-6