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arXiv · 1503.08204

Quantum phase transitions in the Kitaev--Heisenberg model on a single hexagon

Dorota Gotfryd·Andrzej M. Oleś
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Abstract

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 Néel phase and frustrated one which evolves towards the Kitaev spin liquid.

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Dorota Gotfryd, Andrzej M. Oleś. 2015-03-27. Quantum phase transitions in the Kitaev--Heisenberg model on a single hexagon. https://doi.org/10.12693/aphyspola.127.318

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