chyphen;axis tunneling in multilayers NdBa2Cu3O7minus;dgr;junctions with PrBa2Cu3O7minus;dgr;barriers

摘要

This letter reportschyphen;axis tunneling spectroscopy investigations of high quality junctions fabricated fromchyphen;axis oriented NdBa2Cu3O7minus;dgr;/PrBa2Cu3O7minus;dgr;/NdBa2Cu3O7minus;dgr;multilayers deposited by pulsed laser deposition. The conductance spectra as a function of temperature show a smooth crossover from tunneling to metallic junction behavior. A temperature dependent BCShyphen;like gap giving 2Dgr;/kBTc=6 was observed. The currentndash;voltage characteristics exhibit supercurrent and quasiparticle tunneling that is commonly observed for superconductorndash;insulatorndash;superconductor junctions. copy;1996 American Institute of Physics.