Double exchange-driven spin pairing at the (001) surface of manganites
Materials Science
2009-10-31 v1
Abstract
The (001) surface of La_{1-x}Ca_xMnO_3 system in various magnetic orderings is studied by first principle calculations. A general occurrence is that z^2 dangling bond charge -- which is ``invisible'' in the formal valence picture -- is promoted to the bulk gap/Fermi level region. This drives a double-exchange-like process that serves to align the surface Mn spin with its subsurface neighbor, regardless of the bulk magnetic order. For heavy doping, the locally ``ferromagnetic'' coupling is very strong and the moment enhanced by as much as 30% over the bulk value.
Cite
@article{arxiv.cond-mat/0001373,
title = {Double exchange-driven spin pairing at the (001) surface of manganites},
author = {Alessio Filippetti and Warren E. Pickett},
journal= {arXiv preprint arXiv:cond-mat/0001373},
year = {2009}
}
Comments
6 pages, 4 figures