The effect of magnetic (phase) inhomogeneities upon the low temperature conductivity of antiferromagnetic La_{2}CuO_{4+\delta} single crystal

TL;DR

This paper investigates how magnetic inhomogeneities and oxygen distribution affect low-temperature conductivity in La_{2}CuO_{4+ extdelta} single crystals, revealing isolated superconducting regions and magnetic phases.

Contribution

It demonstrates the impact of oxygen inhomogeneity on superconducting inclusions and magnetic phases in La_{2}CuO_{4+ extdelta} at low temperatures.

Findings

Inhomogeneous oxygen distribution creates isolated superconducting inclusions.

Conductivity behavior suggests the presence of a magnetic spin density wave phase.

Superconducting regions form with a hole concentration no more than 0.0024 per Cu.

Abstract

It is found that a strong inhomogeneous distribution of oxygen in single crystal La_{2}CuO_{4+\delta} can lead to the formation of isolated superconducting inclusions, the average hole concentration being no more than 0.0024 per Cu atom. The behavior of the conductivity in the magnetic field below T=20 K is consistent with possible existence of a insulating low-temperature magnetic phase (spin density waves), which is typical of cuprates with excess oxygen.