Static properties of two- and three-dimensional superconducting constrictions

✍ Scribed by J. E. Mooij; P. Dekker

• Publisher: Springer US
• Year: 1978
• Tongue: English
• Weight: 908 KB
• Volume: 33
• Category: Article
• ISSN: 0022-2291
• DOI: 10.1007/bf00115575

✦ Synopsis

Calculations have been performed on superconducting constrictions with hyperbolic geometry. Stationary Ginzburg-Landau equations are used, neglecting magnetic fields. Emphasis is placed on the difference between twoand three -dimensional constrictions, which is related to the difference between uniform-thickness (UT) and variable-thickness (VT) superconducting microbridges. The width of the constriction w, normalized to the coherence length ~, is indicated by the parameter A (---w/2sc). It is found that small (A < O. 1 ), three-dimensional constrictions and VT bridges have a sinusoidal current-phase relation, linear temperature dependence of the critical current Ic, and an IcR product (R is the normal state resistance) equal to the Ambegaokar-Baratoff expression for Josephson junctions near To. Twodimensional constrictions behave as if they consist of an inner core with junction properties, in series with the films on both sides. The core consists of the region within a coherence length from the center of the structure. This size is temperature dependent. The core shows a sinusoidal current-phase relation and LR according to Ambegaokar and Baratoff. For the whole constriction