Dynamics of Fluxon Lattice in Two Coupled Josephson Junctions

TL;DR

This paper theoretically investigates the dynamics of fluxon lattices in two coupled Josephson junctions, revealing resonances, lattice reconstructions, and the excitation of localized nonlinear distortions that can carry magnetic flux.

Contribution

It introduces a detailed theoretical analysis of fluxon lattice behavior, including resonance phenomena and nonlinear excitations in coupled Josephson junctions.

Findings

Resonances occur at specific fluxon velocities related to collective modes.

A reconstruction of the fluxon lattice happens within a certain velocity interval.

Localized nonlinear distortions can be excited and propagate, carrying magnetic flux.

Abstract

We study theoretically the dynamics of a fluxon Lattice (FL) in two coupled Josephson junctions. We show that when the velocity of the moving FL exceeds certain values $(V_{a,b})$, sharp resonances arise in the system which are related to the excitation of the optical and acoustic collective modes. In the interval $(V_a, V_b)$ a reconstruction of the FL occurs. We also establish that one can excite localized nonlinear distortions (dislocations) which may propagate through the FL and carry an arbitrary magnetic flux.