Kink motion in a curved Josephson junction

Abstract

The propagation of the kink along the curved Josephson junction is considered. It is shown that the torsion as well as curvature is responsible for the existence of the energy barrier that affects the motion of the fluxon in the junction. It is also observed that the motion of the kink in the junction can be controlled in a very simple way even in the straight junction by modulating its width.

Kink Profile in a Curved Space

“…In the present paper, we confirmed, on the background of the field model, predictions of the collective coordinate method [9]. Moreover, we found more subtle effects which are present in the regime where the collective coordinate method cannot be applied.…”

“…Let us notice that formula (9) shows that the potential energy stored in the static configuration is bounded from below, it motivates the existence of the static solutions. Moreover, as the kinetic energy is positive, the same argument holds for time-dependent configurations.…”

“…The evolution of the kink in the curved 1d sine-Gordon model was studied in the paper [9] in the framework of the collective coordinate method. In order to use this method, one puts the kink ansatz into the Lagrangian written in curved coordinates and then integrates out all the space variables.…”

“…In particular, we observed formation of the shock waves in the process of collision of ultra-fast kinks with a curved region of the space. Additionally, we explored aspects of evolution which are absent in the collective coordinate approach presented in paper [9]. An example of such a process is shown in Fig.…”

“…This paper shows that for slowly varying curvatures,s the appropriate 1+1 dimensional model correctly describes curved Josephson junctions. The studies of the influence of the nontrivial shape of the Josephson junction on the kink motion were also undertaken in papers [7][8][9].…”