Phase-sticking in one-dimensional Josephson Junction Chains

TL;DR

This paper investigates the current-voltage behavior of long one-dimensional Josephson junction chains with high Josephson energy, revealing a temperature-independent chain current that is modeled using a capacitively shunted junction with nonlinear damping.

Contribution

It provides experimental evidence and a theoretical model for the temperature-independent chain current in Josephson junction chains with high Josephson energy.

Findings

Chain current is voltage-independent at high bias.

Chain current is temperature-independent up to T_C.

Model using capacitively shunted junction with nonlinear damping fits the data.

Abstract

We studied current-voltage characteristics of long one dimensional Josephson junction chains with Josephson energy much larger than charging energy, $E_J \gg E_C$. In this regime, typical IV curves of the samples consist of a supercurrent branch at low bias voltages followed by a voltage-independent chain current branch, $I_{Chain}$ at high bias. Our experiments showed that $I_{Chain}$ is not only voltage-independent but it is also practically temperature-independent up to $T_C$. We have successfully model the transport properties in these chains using a capacitively shunted junction model with nonlinear damping.