Modeling of the vortex dynamics in long Josephson junction

Abstract

We have developed a theoretical model describing the dynamics of the Josephson vortices in the long planar Josephson junction under the influence of the alternating heterogeneous magnetic field created by the tip of magnetic force microscope (MFM), and external uniform, constant magnetic field. The fitting of the model parameters ensured the coincidence of the calculated dependencies of the junction critical current on the external magnetic field with the experimental data, with a standard deviation of less than 0.1 percent. We considered the range of values of the field corresponding to the penetration of more than 10 Josephson vortices at different positions of the MFM tip. From comparison with the experiment, we obtained the estimates of Josephson length, effective area of the junction, critical current distribution along the junction boundary, inductance of the lead wires of the experimental sample and the distribution of the magnetic flux inside the junction created by the MFM tip.