Magnetic interference patterns in superconducting junctions: Effects of anharmonic current-phase relations

Yu. S. Barash

Institute of Solid State Physics, Russian Academy of Sciences - Chernogolovka, Moscow District, 142432 Russia

Received: 12 May 2010
Accepted: 21 July 2010

Abstract

A microscopic theory of the magnetic-field modulation of critical currents is developed for plane Josephson junctions with anharmonic current-phase relations. The results obtained allow examining temperature-dependent deviations of the modulation from the conventional interference pattern. For tunneling through localized states in symmetric short junctions with a pronounced anharmonic behavior, the deviations are obtained and shown to depend on the distribution of channel transparencies. For constant transparency the deviations vanish not only near T_c, but also at T=0. If Dorokhov bimodal distribution for transparency eigenvalues holds, the averaged deviation increases with decreasing temperature and takes its maximum at T=0.