Experimental Evidence of a φ Josephson Junction

被引：122

作者：

Sickinger, H. ^{[1
,2
]}

Lipman, A. ^{[3
]}

Weides, M. ^{[4
,5
]}

Mints, R. G. ^{[3
]}

Kohlstedt, H. ^{[6
]}

Koelle, D. ^{[1
,2
]}

Kleiner, R. ^{[1
,2
]}

Goldobin, E. ^{[1
,2
]}

机构：

[1] Univ Tubingen, Inst Phys, D-72076 Tubingen, Germany

[2] Univ Tubingen, Ctr Collect Quantum Phenomena LISA, D-72076 Tubingen, Germany

[3] Tel Aviv Univ, Raymond & Beverly Sackler Sch Phys & Astron, IL-69978 Tel Aviv, Israel

[4] Forschungszentrum Julich, Peter Grunberg Inst, D-52425 Julich, Germany

[5] Forschungszentrum Julich, JARA Fundamentals Future Informat Technol, D-52425 Julich, Germany

[6] Univ Kiel, Tech Fak, D-24143 Kiel, Germany

来源：

PHYSICAL REVIEW LETTERS | 2012年 / 109卷 / 10期

关键词：

SUPERCONDUCTORS; FLUX; SUPERCURRENT; FERROMAGNET; SYMMETRY; STATE;

D O I：

10.1103/PhysRevLett.109.107002

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We demonstrate experimentally the existence of Josephson junctions having a doubly degenerate ground state with an average Josephson phase psi = +/-phi. The value of phi can be chosen by design in the interval 0 < phi < pi. The junctions used in our experiments are fabricated as 0-pi Josephson junctions of moderate normalized length with asymmetric 0 and pi regions. We show that (a) these phi Josephson junctions have two critical currents, corresponding to the escape of the phase c from -phi and +phi states, (b) the phase psi can be set to a particular state by tuning an external magnetic field, or (c) by using a proper bias current sweep sequence. The experimental observations are in agreement with previous theoretical predictions.

引用

页数：5

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