Exchange Frequencies in the 2d Wigner crystal
Strongly Correlated Electrons
2009-10-31 v1
Abstract
Using Path Integral Monte Carlo we have calculated exchange frequencies as electrons undergo ring exchanges in a ``clean'' 2d Wigner crystal as a function of density. The results show agreement with WKB calculations at very low density, but show a more rapid increase with density near melting. Remarkably, the exchange Hamiltonian closely resembles the measured exchanges in 2d He. Using the resulting multi-spin exchange model we find the spin Hamiltonian for r_s \leq 175 \pm 10 is a frustrated antiferromagnetic; its likely ground state is a spin liquid. For lower density the ground state will be ferromagnetic.
Keywords
Cite
@article{arxiv.cond-mat/0008062,
title = {Exchange Frequencies in the 2d Wigner crystal},
author = {B. Bernu and Ladir Candido and D. M. Ceperley},
journal= {arXiv preprint arXiv:cond-mat/0008062},
year = {2009}
}