Degradation-free interfaces in MgB2/insulator/Pb Josephson tunnel junctions

被引：27

作者：

Cui, Y.

Chen, Ke

Li, Qi

Xi, X. X.

Rowell, J. M.

机构：

[1] Penn State Univ, Dept Phys, University Pk, PA 16802 USA

[2] Penn State Univ, Dept Mat Sci & Engn, University Pk, PA 16802 USA

[3] Arizona State Univ, Dept Chem & Mat Engn, Tempe, AZ 85287 USA

来源：

APPLIED PHYSICS LETTERS | 2006年 / 89卷 / 20期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1063/1.2388891

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

High quality superconductor-barrier interfaces are critical for Josephson tunnel junctions. The authors show that such interfaces can be achieved in MgB2/insulator/Pb trilayer junctions using MgB2 films grown by hybrid physical-chemical vapor deposition and with barriers formed at elevated temperatures. The junctions show clear Josephson tunneling characteristics with high J(c) (similar to 3 kA/cm(2)), high IcRN products (similar to 1.9 meV), and the expected I-c(B) pattern. The observed pi gap is small (2.0 meV) and the sigma gap is large (7.4 meV), in agreement with theoretical predictions and indicating that the superconducting property of MgB2 is not degraded at the MgB2-insulator interface. (c) 2006 American Institute of Physics.

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