Magnetoresistance of the Double-Exchange Model in Infinite Dimension

TL;DR

This paper analyzes the double-exchange model in infinite dimensions, deriving analytical expressions for key quantities and successfully reproducing magnetoresistance observed in lightly doped manganites.

Contribution

It provides analytical solutions for the double-exchange model in infinite dimensions and demonstrates its effectiveness in modeling experimental magnetoresistance.

Findings

Analytical forms for Green's function and conductivity derived.

Reproduces magnetoresistance in lightly doped (La,Sr)MnO₃.

Validates the infinite-dimensional limit for this model.

Abstract

Double-exchange model in infinite dimension is studied as the strong Hund's coupling limit $J\to\infty$ of the Kondo lattice model. Several quantities such as Green's function and the d.c.\ conductivity are calculated in analytical forms. Magnetoresistance in lightly doped (La,Sr)MnO$_3$ is reproduced very well.