Entropy Driven Dimerization in a One-Dimensional Spin-Orbital Model
强关联电子
2007-05-23 v1
摘要
We study a new version of the one-dimensional spin-orbital model with spins S=1 relevant to cubic vanadates. At small Hund's coupling J_H we discover dimerization in a pure electronic system solely due to a dynamical spin-orbital coupling. Above a critical value J_H, a uniform ferromagnetic state is stabilized at zero temperature. More surprisingly, we observe a temperature driven dimerization of the ferrochain, which occurs due to a large entropy released by dimer states. This dynamical dimerization seems to be the mechanism driving the peculiar intermediate phase of YVO_3.
引用
@article{arxiv.cond-mat/0212368,
title = {Entropy Driven Dimerization in a One-Dimensional Spin-Orbital Model},
author = {J. Sirker and G. Khaliullin},
journal= {arXiv preprint arXiv:cond-mat/0212368},
year = {2007}
}
备注
5 pages, 4 figures