Antiferromagnetic Order in Disorder-Induced Insulating Phase of SrRu_{1-x}Mn_xO_3 (0.4<x<0.6)

TL;DR

This study reveals that Mn substitution in SrRuO_3 induces a transition from itinerant ferromagnetism to localized antiferromagnetic order, with enhanced magnetic moments and structural changes, highlighting the impact of disorder on magnetic phases.

Contribution

It demonstrates the emergence of C-type antiferromagnetic order in SrRu_{1-x}Mn_xO_3 for 0.4<x<0.6, showing how Mn substitution alters magnetic and electronic properties.

Findings

Transition from ferromagnetic to antiferromagnetic order with Mn doping

Increase in AF moment from 1.1 to 2.6 μB as x increases

Similar magnetic and transport properties in tetragonal and orthorhombic phases

Abstract

We have performed the powder neutron diffraction measurements on the solid solutions of SrRu_{1-x}Mn_xO_3, and found that the itinerant ferromagnetic order observed in pure SrRuO_3 changes into the C-type antiferromagnetic (AF) order with nearly localized d electrons in the intermediate Mn concentration between x=0.4 and 0.6. With increasing x, the AF moment is strongly enhanced from 1.1 mB (x=0.4) to 2.6 mB (x=0.6), which is accompanied by the elongation of the tetragonal c/a ratio. These results suggest that the substitution of Mn for Ru suppresses the itinerant character of the d electrons, and induces the superexchange interaction through the compression in the c plane. We have also found that the magnetic and transport properties observed in our tetragonal samples are quite similar to those of recently reported orthorhombic ones.