QUASI-PARTICLE-INJECTION EFFECT IN YBA2CU3OX-BASED PLANAR STRUCTURES

The supercurrent I(s) of a YBCO bridge can be modulated by the quasipa rticle-injection current I(G) from YBCO/Au or YBCO/PBCO/Au junctions. The behavior of these structures is determined by two effects: 1) summ ation of the currents I(s) and I(G) in the YBCO bridge; 2) nonequilibr ium suppression of the supercurrent I(s) by the quasiparticle-injectio n. The current gain coefficient DELTAI(S)/DELTAI(G) increases linearly with decreasing temperature, reaching a value of 1.5 for YBCO/Au stru ctures at 65 K. The nature of the nonequilibrium state and the effecti veness of the PBCO barrier layer for the formation of the quasiparticl es are analyzed.