Microwave plasma emission from Bi2Sr2CaCu2Oy tunnel-injected intrinsic Josephson junctions

We report on the novel nonequilibrium microwave emission from quasiparticle-injected high-T-c, superconductors. The phenomena have been observed for the current-injected Bi2Sr2CaCu2Ov (BSCCO)/I/Au thin-film tunnel junctions and BSCCO single-crystal intrinsic Josephson mesa junction samples. For the thin-film tunnel junctions, the emitted radiation appears as broadband. For the intrinsic BSCCO mesa samples, the radiation appears as three different modes of emissions depending on the bias point in the hysteretic current-voltage characteristics; Josephson emission, non-equilibrium broad emission and sharp coherent microwave emission. The results were interpreted by the Josephson plasma excitation model due to quasiparticle injection. (C) 2002 Elsevier Science B.V. All rights reserved.