We present a detailed analysis of the Kitaev--Heisenberg model on a single hexagon. The energy spectra and spin--spin correlations obtained using exact diagonalisation indicate quantum phase transitions between antiferromagnetic and anisotropic spin correlations when the Kitaev interactions increase. In cluster mean-field approach frustrated nearest neighbor exchange stabilizes the stripe phase in between the N\'eel phase and frustrated one which evolves towards the Kitaev spin liquid.
@article{arxiv.1503.08204,
title = {Quantum phase transitions in the Kitaev--Heisenberg model on a single hexagon},
author = {Dorota Gotfryd and Andrzej M. Oleś},
journal= {arXiv preprint arXiv:1503.08204},
year = {2015}
}
Comments
3 pages, 3 figures, Euroconference Physics of Magnetism, Pozna\'n 2014