HIGH-QUALITY NB/ALOX-AL/NB JOSEPHSON-JUNCTIONS WITH GAP VOLTAGE OF 2.95-MV

被引：3

作者：

KUSUNOKI, M

YAMAMORI, H

FUJIMAKI, A

TAKAI, Y

HAYAKAWA, H

机构：

[1] Department of Electronics, Nagoya University, Nagoya, 464-01, Furo-cho Chikusa-ku

来源：

JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS | 1993年 / 32卷 / 11A期

关键词：

JOSEPHSON JUNCTION; NB/ALOX-AL/NB TRILAYER; GAP VOLTAGE; IMPURITIES; DEPOSITION RATE; GRAIN SIZE; THIN AL LAYER; GAP WIDTH;

D O I：

10.1143/JJAP.32.L1609

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The dependence of the gap voltage on impurities in Nb films is studied. The gap voltage is determined by the number of impurities included in the films. The impurities arise from the residual gas in the sputtering chamber before the deposition of Nb films. By reducing the impurities in the films, we obtain high-quality Nb/AlO(x)-Al/Nb Josephson junctions having the gap voltage of 2.95 mV which is close to that estimated from the energy gap of Nb bulk at 4.2 K. In addition, the use of a thin Al layer is also an important factor in obtaining excellent current-voltage characteristics.

引用

页码：L1609 / L1611

页数：3

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