New quantum phase transitions in the two-dimensional J1-J2 model
Abstract
We analyze the phase diagram of the frustrated Heisenberg antiferromagnet, the J1-J2 model, in two dimensions. Two quantum phase transitions in the model are already known: the second order transition from the Neel state to the spin liquid state at (J_2/J_1)_{c2}=0.38, and the first order transition from the spin liquid state to the collinear state at (J_2/J_1)_{c4}=0.60. We have found evidence for two new second order phase transitions: the transition from the spin columnar dimerized state to the state with plaquette type modulation at (J_2/J_1)_{c3}=0.50(2), and the transition from the simple Neel state to the Neel state with spin columnar dimerization at (J_2/J_1)_{c1}=0.34(4). We also present an independent calculation of (J_2/J_1)_{c2}=0.38 using a new approach.
Keywords
Cite
@article{arxiv.cond-mat/0007329,
title = {New quantum phase transitions in the two-dimensional J1-J2 model},
author = {O. P. Sushkov and J. Oitmaa and Zheng Weihong},
journal= {arXiv preprint arXiv:cond-mat/0007329},
year = {2009}
}
Comments
3 pages, 5 figures; added reference