Distorted Perovskite with e_g^1 Configuration as a Frustrated Spin System

TL;DR

This paper investigates the complex spin and orbital ordering in distorted perovskite manganites with an $e_g^1$ configuration, revealing how structural distortions induce frustrated interactions leading to unique antiferromagnetic states.

Contribution

It demonstrates how GdFeO$_3$-type distortions in $R$MnO$_3$ induce anisotropic interactions, resulting in novel sinusoidal and E-type antiferromagnetic orders.

Findings

Identification of frustrated spin systems in distorted perovskites

Correlation between structural distortion and magnetic ordering

Discovery of unique sinusoidal and E-type antiferromagnetic states

Abstract

The evolution of spin- and orbital-ordered states has been systematically investigated for a series of insulating perovskites $R$MnO$_3$ ($R$=La,Pr,Nd,...). $R$MnO$_3$ with a large GdFeO$_3$-type distortion is regarded as a frustrated spin system having ferromagnetic nearest-neighbor and antiferromagnetic (AF) next-nearest-neighbor (NNN) interactions within a MnO$_2$ plane. The staggered orbital order associated with the GdFeO$_3$-type distortion induces the anisotropic NNN interaction, and yields the unique sinusoidal and $E$-type ("up-up-down-down") AF ordered states in the distorted perovskites with $e_g^1$ configuration.