학술논문
Phase diagram of half-doped manganites
Document Type
Journal Article
Author
Source
Physical Review B; 63; 22; Other Information: DOI: 10.1103/PhysRevB.63.224409; Othernumber: PRBMDO000063000022224409000001; 085122PRB; PBD: 1 Jun 2001
Subject
Language
English
ISSN
0163-1829
Abstract
The phase diagram of half-doped manganites which may consist of experimentally observed ferromagnetic (FM), A-,C-, and charge-exchange (CE)-type antiferromagnetic (AF) states is obtained in terms of a model which is based on double exchange via degenerate e{sub g} orbitals, the on-site Coulomb interaction (U), and the nearest-neighbor Coulomb interaction (V). We find that, because of the strong spatial anisotropy of the electron hoppings, the on-site Coulomb interaction has different effects on these magnetic order states. As a result, large values of U suppress the FM state and favor the A- and C-type AF states. Moreover, we show that it is the interplay between the on-site and nearest-neighbor Coulomb repulsions that stabilizes the CE phase and results in the charge ordering in the state.