YBCOSQUIDs with unconventional current phase relation
Journal article, 2007

We have studied the dynamics of YBa2Cu3O7-delta,5 (YBCO) dc sperconducting quantum interference devices (SQUIDs) characterized by an unconventional Josephson current phase relation (CPR). We have focused on SQUID configurations with Josephson junctions where the lobe of the order parameter in one electrode is facing a node in the other electrode. This order parameter arrangement should enhance the appearance of a sin(2(p) term in the CPR. The response of the critical current of the dc SQUID, under the effect of an external magnetic field, has been measured in temperature, down to 20 mK. Our experimental data have been compared with numerical simulations of the SQUIDs dynamics by considering a CPR of a single junction of the form I(phi) = I-I sin(phi) - I-II sin(2 phi) where I-I, and I-II are, respectively, the first and second harmonic component. In our devices the values of the sin(2 phi) term are such that the fundamental state of the SQUID is naturally double degenerate. This is of great relevance for applications of d-wave SQUIDs in quantum information processing. (C) 2007 Elsevier B.V. All rights reserved.

Author

Thilo Bauch

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Jesper Johansson

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Karin Cedergren

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Tobias Lindström

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Floriana Lombardi

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Physica C: Superconductivity and its Applications

0921-4534 (ISSN)

Vol. 463-465 1 October 2007 979-984

Subject Categories

Physical Sciences

DOI

10.1016/j.physc.2007.03.475

More information

Created

10/6/2017