Distinct Magnetic Phases in Structurally Uniform SrCoO$_{3-y}$

TL;DR

This study reveals that SrCoO$_{3-y}$ exhibits two distinct magnetic phases coexisting in a spatially separated manner, linked to variations in local charge density, with implications for understanding phase separation in correlated oxides.

Contribution

The paper demonstrates, using muon spin rotation and neutron scattering, that two magnetic transitions in SrCoO$_{3-y}$ correspond to separate phases with different charge densities, a novel insight into its phase behavior.

Findings

Two magnetic phases coexist in SrCoO$_{3-y}$.

The phases are spatially distinct and linked to charge density variations.

The phase separation occurs at an intermediate length scale.

Abstract

Two magnetic phase transitions have been noted for SrCoO$_{3-y}$ for near-stoichiometric oxygen concentrations (small y). Using muon spin rotation and neutron scattering experiments, we have established that the two transitions represent separate, spatially distinct magnetic phases that coexist in a two-phase equilibrium mixture. The two phases most likely represent areas of the sample with different effective valence charge density. Further, the phases exist over regions with a length scale intermediate between nanoscale charge inhomogeneity and systems such as manganites or super-oxygenated cuprates with large length scale phase separation.