Coordinate transformation in the model of long Josephson junctions: geometrically equivalent Josephson junctions

E. G. Semerdzhieva; T. L. Boyadjiev; Yu. M. Shukrinov

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Coordinate transformation in the model of long Josephson junctions: geometrically equivalent Josephson junctions

E. G. Semerdzhieva·T. L. Boyadjiev·Yu. M. Shukrinov

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Abstract

The transition from the model of a long Josephson junction of variable width to the model of a junction with a coordinate-dependent Josephson current amplitude is effected through a coordinate transformation. This establishes the correspondence between the classes of Josephson junctions of variable width and quasi-one-dimensional junctions with a variable thickness of the barrier layer. It is shown that for a junction of exponentially varying width the barrier layer of the equivalent quasi-one-dimensional junction has a distributed resistive inhomogeneity that acts as an attractor for magnetic flux vortices. The curve of the critical current versus magnetic field for a Josephson junction with a resistive microinhomogeneity is constructed with the aid of a numerical simulation, and a comparison is made with the critical curve of a junction of exponentially varying width. The possibility of replacing a distributed inhomogeneity in a Josephson junction by a local inhomogeneity at the end of the junction is thereby demonstrated; this can have certain advantages from a technological point of view.

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E. G. Semerdzhieva, T. L. Boyadjiev, Yu. M. Shukrinov. 2006-03-16. Coordinate transformation in the model of long Josephson junctions: geometrically equivalent Josephson junctions. https://arxiv.org/abs/cond-mat/0603439

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