Orbital ordering in manganites in the band approach
Strongly Correlated Electrons
2009-11-10 v1 Statistical Mechanics
Abstract
We consider the orbital ordering in LaMnO3 and similar systems, proceeding from the band picture. We show that for the realistic magnetic structure of A-type there exists a complete nesting betweeen two e_g-bands. As a result there occurs an instability towards an excitonic insulator-like state -- an electron-hole pairing with the wave vector Q=(\pi,\pi), which opens a gap in the spectrum and makes the system insulating. In the resulting state there appeasr an orbital ordering -- orbital density wave (ODW), the type of which coincides with those existing in LaMnO3.
Cite
@article{arxiv.cond-mat/0407656,
title = {Orbital ordering in manganites in the band approach},
author = {D. V. Efremov and D. I. Khomskii},
journal= {arXiv preprint arXiv:cond-mat/0407656},
year = {2009}
}
Comments
4 pages, 2 figures