A-b plane microwave surface impedance of a high-quality Bi2Sr2CaCu2O8 single crystal

Abstract

The a-b plane microwave surface impedance of a high-quality Bi2Sr2CaCu2O8 single crystal \(Tc∼93 K\) has been measured at 14.4, 24.6, and 34.7 GHz. The surface resistance at low temperature is the lowest yet reported, is comparable with the best YBa2Cu3O7-δ data, and has a characteristic ω2 frequency dependence. The change in penetration depth, Δλab\(T\), has a strong linear term at low temperature which is consistent with a gap with line nodes on the Fermi surface. The real part of the microwave conductivity displays a broad peak at low temperature, similar to that observed in YBa2Cu3O7-δ. © 1996 The American Physical Society.