The resistance anomaly in the surface layer of Bi 2Sr 2CaCu 2O 8+ x single crystals under radio-frequency irradiation

Abstract

We observed that radio-frequency (rf) irradiation significantly enhances the c-axis resistance near and below the superconducting transition of the CuO 2 layer in contact with a normal-metal electrode on the surface of Bi 2Sr 2CaCu 2O 8+ x single crystals. We attribute the resistance anomaly to the rf-induced charge imbalance nonequilibrium effect in the surface CuO 2 layer. The relaxation of the charge-imbalance in this highly anisotropic system is impeded by the slow quasiparticle recombination rate, which results in the observed excessive resistance.