Andreev-reflection in YBCO-single crystal break-junctions

✍ Scribed by U. Zimmermann; D. Dikin; S. Abens; K. Keck; T. Wolf

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 146 KB
• Volume: 235-240
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(94)92172-5

✦ Synopsis

We will discuss m this paper YBCO point contact measurements showing the lndwations of multiple Andreev reflect ion (A R) in terms of su bharmonic-gap struct ure (SGS) and excess-curren t The point-contacts are realized by the well known brealx-junctmn technique They are prepared by cutting mechanically bridges of a diameter < ll)0pm in YBCO-~lngle crystals followed by a breaking of the bridges in Llle [4] In general the possible occurrence of multiple AR m break junctions is shown in [6] for Nb We will compare the mea~ured i(V) and ~f(V)-char~cter~stics with such ones of Pb/n-lnSb/Pb-junctions, which we are investigating too l,t [1] we discussed the characteristics of these conventmnM contacts m comparison with the OTBK-theory [2] There we pointed out some substantial differences between theory and experiment. Here we will concentrate on the conlpan~on of the conventional with HTSC contacts espeoally under the irradiation of externM rf-fields