YBCOSQUIDs with unconventional current phase relation
Artikel i vetenskaplig tidskrift, 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.

Författare

Thilo Bauch

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Jesper Johansson

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Karin Cedergren

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Tobias Lindström

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Floriana Lombardi

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Physica C: Superconductivity and its Applications

0921-4534 (ISSN)

Vol. 463-465 1 October 2007 979-984

Ämneskategorier

Fysik

DOI

10.1016/j.physc.2007.03.475

Mer information

Skapat

2017-10-06