A theory of \pi/2 superconducting Josephson junctions

TL;DR

This paper presents a theoretical model of  superconducting Josephson junctions with randomly signed critical current density, revealing a ground state with a phase difference of , relevant for superconductor-ferromagnet junctions.

Contribution

It introduces a novel theoretical framework for understanding  Josephson junctions with random sign variations in critical current density.

Findings

Ground state corresponds to phase difference of 

Applicable to superconductor-ferromagnet junctions

Provides insight into phase behavior with random critical current signs

Abstract

We consider theoretically a Josephson junction with a superconducting critical current density which has a random sign along the junction's surface. We show that the ground state of the junction corresponds to the phase difference equal to \pi/2. Such a situation can take place in superconductor- ferromagnet junction.