Spin Driven Jahn-Teller Distortion in a Pyrochlore system
Strongly Correlated Electrons
2009-10-31 v1
Abstract
The ground-state properties of the spin-1 antiferromagnetic Heisenberg model on the corner-sharing tetrahedra, pyrochlore lattice, is investigated. By breaking up each spin into a pair of 1/2-spins, the problem is reduced to the equivalent one of the spin-1/2 tetrahedral network in analogy with the valence bond solid state in one dimension. The twofold degeneracy of the spin-singlets of a tetrahedron is lifted by a Jahn-Teller mechanism, leading to a cubic to tetragonal structural transition. It is proposed that the present mechanism is responsible for the phase transition observed in the spin-1 spinel compounds ZnVO and MgVO.
Cite
@article{arxiv.cond-mat/0010504,
title = {Spin Driven Jahn-Teller Distortion in a Pyrochlore system},
author = {Yasufumi Yamashita and Kazuo Ueda},
journal= {arXiv preprint arXiv:cond-mat/0010504},
year = {2009}
}
Comments
4 pages, 3 eps figures, REVTeX, to appear in Phys. Rev. Lett