Weak magnetic order in high-Tc superconductors produced by spontaneous Josephson currents

TL;DR

This paper proposes a model for high-Tc superconductors where spontaneous Josephson currents due to frustration cause weak magnetic order, aligning with observed experimental behaviors.

Contribution

It introduces a novel model linking electronic phase separation and Josephson junction frustration to weak magnetic order in cuprates.

Findings

Reproduces the onset of spontaneous magnetic signals.

Explains the doping dependence of magnetic order.

Connects weak magnetism to Josephson current frustration.

Abstract

We develop a model for high-Tc superconductors based on an electronic phase separation where low-and high-density domains are formed. At low temperatures this system may act as a granular superconductor forming an array of Josephson junctions. Cuprates are also known to have low superfluid densities and strong correlation effects. Both characteristics activate a negative Josephson coupling due to frustration that leads to spontaneous currents responsible for the weak ferromagnetic order. This original approach reproduces the observed onset of spontaneous magnetic signal and its dependence on the doping level.