Peculiarities in Low Temperature Properties of Doped Manganites A1-xBxMnO3

TL;DR

This paper analyzes the phase diagram and low temperature properties of doped manganites A1-xBxMnO3, focusing on the transition from insulating to metallic states around x=0.16, using theoretical models and experimental comparisons.

Contribution

It provides a unifying theoretical description of insulating and metallic phases in doped manganites, including the transition mechanism and low temperature behaviors.

Findings

Transition from insulator to metal at x=0.16

Describes insulating phase as band insulator with ferromagnetic layers

Metallic phase modeled by two-band Fermi liquid

Abstract

The phase diagram and low temperature properties of the doped manganites A1-xBxMnO3 are discussed for the concentrations x < 0.4. The transition from insulating antiferromagnetic to metallic ferromagnetic state at x_cr = 0.16 is treated by means of percolation theory. The unifying description of insulating and metallic states is presented. The undoped manganite is a band insulator consisting of ferromagnetic layers, which are coupled antiferromagnetically along the c direction with a low Neel temperature. The metallic phase can be described by the two-band Fermi liquid picture. The behavior of conductivity, spin wave excitations, etc. is analyzed and the comparison with experimental data is carried out.