Tunneling Studies of BaPb_<0.75>Bi_<0.25>O_3

概要

論文の詳細を見る
The tunneling spectroscopy was performed for the Ag or l'b-SiO-Ba Pb...,Bi...,O.(referred to BPBO) planer junction. For the junction with the Ag electrode, thesuperconducting-gap (2A) is equal to 3.2 meV and 2Ag/k.T. to 3.6. It was found thatwhen a value of A is determined so that the temperature dependence of A agrees withthe one of BCS theory, tlae temperature dependence of a recombination time of aquasiparticle largely deviates from the one of BCS theory. I'he deviation is explainedby a fact that the V - cll/ d V characteristic contains a component of a leak-currentbeside a tunnel one. While, for the junction witln the Pb electrode, it was found that2A at 4.2 K is equal to 9 men. This large value comes from a zero-bias anomaly. Theincrease of a slope toward zero-bias in the V - d I / d V cltaraeteristic suggests that theenergy band near the Fermi energy in BPBO is strongly noxtparabolic and has a gapcaused by the charge density wave.tunneling spectroscopy, s;uperconductor, BaPb.,Bi..,0.
社団法人日本物理学会の論文
1992-09-15