Journal of Physics Conference Series

Excitation spectra of the one-dimensional double-exchange model: An exact solution for one mobile electron

K Nakano, R. Eder, Y. Ohta

Published Dec 17, 2012• 0 citations

Abstract

We study the one-dimensional double-exchange model with L localized spins and one mobile electron. We solve the Schrödinger equation analytically and obtain the energies and wave functions for all the eigenstates with spin S = ( L − 1)***/2 exactly. As an application, we compute the single-particle Green's function. We show that, for vanishing exchange interactions between localized spins, the single-particle spectrum is entirely incoherent and the lowest band has an infinite band mass, i.e., the single electron is localized due to its interaction with the spin excitations. The analysis of the wave function gives us a particularly simple ground state.

DOI: 10.1088/1742-6596/400/3/032066

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