Temperature dependence of superconducting gaps in Mg1-xAlxB2 system investigated by SnS-Andreev spectroscopy

被引：18
|
作者：
Kuzmichev, S. A. [1 ]
Shanygina, T. E. [1 ,2 ]
Tchesnokov, S. N. [1 ]
Krasnosvobodtsev, S. I. [2 ]
机构：
[1] Moscow MV Lomonosov State Univ, Moscow 119991, Russia
[2] RAS, PN Lebedev Phys Inst, Moscow 119991, Russia
来源：
SOLID STATE COMMUNICATIONS | 2012年 / 152卷 / 02期
关键词：
High-T-C superconductors; Tunneling; Multiple Andreev reflections; POINT-CONTACT; TUNNELING EXPERIMENTS; T-C; MGB2; SCATTERING; TRANSITION; JUNCTIONS; AL;
D O I：
10.1016/j.ssc.2011.10.028
中图分类号：
O469 [凝聚态物理学];
学科分类号：
070205 ;
摘要：
Detailed temperature dependence of both superconducting gaps was obtained directly by means of SnS-Andreev spectroscopy. The Delta(sigma,pi)(T)-curves were shown to be deviated from standard BCS-like behavior, due to k-space proximity effect between alpha- and pi-condensates, which could give a key to experimental determination of interband electron-phonon coupling constants. For the first time, an excellent qualitative agreement with theoretical predictions of Nicol and Carbotte, and Moskalenko and Suhl was shown. dl(V)/dV-spectra of SnS-Andreev contacts based on MgB2 samples (with defects of crystal structure), and Mg1-xAlxB2 polycrystalline samples (with the local critical temperature T-C variation 10 K <= T-C <= 37 K) were studied by means of the "break-junction" technique within the temperature range 4.2 K <= T <= T-C. (C) 2011 Elsevier Ltd. All rights reserved.
引用
收藏
页码：119 / 122
页数：4
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