First-Order Phase Transitions in Frustrated Spin Systems
Abstract
We give a short review of our recent works on the first-order quantum phase transitions in frustrated spin chains with orthogonal-dimer structure. When the ratio of the competing antiferromagnetic exchange couplings is varied, a first-order transition occurs between the dimer phase and the plaquette phase, which is accompanied by the discontinuity in the spin excitation gap. We further show that strong frustration triggers the phase transitions in a magnetic field, which exhibit plateaus and jumps in the magnetization curve. The hole-doping effect is also addressed for the orthogonal-dimer chain with linked-tetrahedra structure. It is found that the competing antiferromagnetic interactions result in a first-order metal-insulator transition upon hole doping.
Cite
@article{arxiv.cond-mat/0204505,
title = {First-Order Phase Transitions in Frustrated Spin Systems},
author = {Akihisa Koga and Akira Kawaguchi and Kouichi Okunishi and Norio Kawakami},
journal= {arXiv preprint arXiv:cond-mat/0204505},
year = {2009}
}
Comments
6 pages, 6 figures, to appear in Prog. Theor. Phys. Suppl. Proceedings of the 16th Nishinomiya Yukawa Memorial Symposium