Coherent States of Two-dimensional Josephson Junction Networks

TL;DR

This paper numerically investigates phase-locking in 2D Josephson junction arrays, revealing multi-valued I-V characteristics and hysteretic transitions between coherent states influenced by magnetic flux.

Contribution

It demonstrates the existence of multi-valued I-V curves and hysteretic state transitions in 2D Josephson junction networks considering finite inductance and magnetic fields.

Findings

Existence of multi-valued I-V curves.

Hysteretic transitions between in-phase and anti-phase states.

External magnetic flux influences state transitions.

Abstract

We have investigated numerically the phase--locking behavior of two-dimensional Josephson junction arrays,taking into account a finite inductance ($l\stackrel{>}{\sim}1$) of the unit cell and external magnetic fields. Within this model we demonstrate the existence of multi--valued {\it I--V} curves of the network. Different branches of the {\it I--V} curve correspond to "in--phase" and "anti--phase" coherent states with high and low levels of output power, respectively. The arrays show remarkable hysteretic transitions between these states under influence of external magnetic fluxes in the range $ - \Phi_0/4 < \Phi_{ext} < \Phi_0/4 $.