Phase transitions in spin-orbital coupled model for pyroxene titanium oxides
Abstract
We study the competing phases and the phase transition phenomena in an effective spin-orbital coupled model derived for pyroxene titanium oxides ATiSi2O6 (A=Na, Li). Using the mean-field-type analysis and the numerical quantum transfer matrix method, we show that the model exhibits two different ordered states, the spin-dimer and orbital-ferro state and the spin-ferro and orbital-antiferro state. The transition between two phases is driven by the relative strength of the Hund's-rule coupling to the onsite Coulomb repulsion and/or by the external magnetic field. The ground-state phase diagram is determined. There is a keen competition between orbital and spin degrees of freedom in the multicritical regime, which causes large fluctuations and significantly affects finite-temperature properties in the paramagnetic phase.
Cite
@article{arxiv.cond-mat/0410411,
title = {Phase transitions in spin-orbital coupled model for pyroxene titanium oxides},
author = {Toshiya Hikihara and Yukitoshi Motome},
journal= {arXiv preprint arXiv:cond-mat/0410411},
year = {2015}
}
Comments
4 pages, 6 figures, proceedings submitted to SPQS2004