Randomness Effect on Multicritical Phenomena in Double-Exchange Systems

TL;DR

This study investigates how randomness influences multicritical phenomena in double-exchange systems, revealing bicritical behavior and differing responses to disorder that align with experimental observations in manganites.

Contribution

It introduces a systematic analysis of randomness effects on double-exchange models, highlighting bicritical behavior and state-dependent disorder responses.

Findings

Bicritical behavior between ferromagnetic metal and charge-ordered insulator

Distinct responses to randomness for different states

Agreement with experimental colossal magnetoresistance manganite data

Abstract

Double-exchange model interacting with adiabatic phonons is studied in the presence of randomness by using the Monte-Carlo method and the systematic size-scaling analysis. A bicritical behavior is found between the ferromagnetic metal and the charge-ordered insulator. We find the distinct response to the randomness between these two states, which agrees well with the experimental results in the colossal magnetoresistance manganites.