Spectroscopic evidence for unconventional superconductivity in UBe13

被引：51

作者：

Wälti, C ^{[1
]}

Ott, HR

Fisk, Z

Smith, JL

机构：

[1] ETH Honggerberg, Festkorperphys Lab, CH-8093 Zurich, Switzerland

[2] Natl High Magnet Field Lab, Tallahassee, FL 32306 USA

来源：

PHYSICAL REVIEW LETTERS | 2000年 / 84卷 / 24期

关键词：

D O I：

10.1103/PhysRevLett.84.5616

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We report on measurements of the differential conductivity G of UBe13-Au contacts, which reveal the existence of low-energy Andreev surface bound states. These hound states are identified via huge conducranoe peaks at zero bias that may form only in superconductors with nontrivial energy-gap functions. From the voltage dependence of G at T < T-c we also establish a lower limit of the normalized energy gap, such 2 Delta(0)/k(B)T(c) > 6.7, much in excess of the weak coupling BCS value of 3.5, and directly indicating strong coupling effects in superconducting UBe13.

引用

页码：5616 / 5619

页数：4

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