Influence of coupling between junctions on breakpoint current in intrinsic Josephson junctions

TL;DR

This paper theoretically investigates how coupling between junctions affects the breakpoint current in intrinsic Josephson junctions, revealing oscillations, plasma wave effects, and methods to determine wave numbers.

Contribution

It introduces a theoretical model explaining oscillations in breakpoint current due to plasma wave creation and proposes a method to determine wave numbers from parameter dependencies.

Findings

Oscillations of breakpoint current as a function of coupling and dissipation parameters.

Identification of longitudinal plasma wave creation at the breakpoint.

Good agreement between the model and simulation results.

Abstract

We study theoretically the current-voltage characteristics of intrinsic Josephson junctions in high-$T_c$ superconductors. An oscillation of the breakpoint current on the outermost branch as a function of coupling $\alpha$ and dissipation $\beta$ parameters is found. We explain this oscillation as a result of the creation of longitudinal plasma waves at the breakpoint with different wave numbers. We demonstrate the commensurability effect and predict a group behavior of the current-voltage characteristics for the stacks with a different number of junctions. A method to determine the wave number of longitudinal plasma waves from $\alpha$- and $\beta$-dependence of the breakpoint current is suggested. We model the $\alpha$- and $\beta$-dependence of the breakpoint current and obtain good agreement with the results of simulation.