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arXiv · 1101.1388

Spin correlations and phase diagram of the perturbed Kitaev model

S. Mandal·Subhro Bhattacharjee·K. Sengupta·R. Shankar·G. Baskaran
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Abstract

We present a general classification of the perturbations to the Kitaev model on the basis of their effect on it's spin correlation functions. We derive a necessary and sufficient condition for the spin correlators to exhibit a long ranged power-law behavior in the presence of such perturbations. We substantiate our result by a study of the phase diagram of the Kitaev model augmented by a loop term and perturbed by an Ising term, within a RVB mean-field theory. We estimate the stability of the spin-liquid phase against such perturbations and show that this model exhibits both confinement-deconfinement transitions from spin liquid to antiferromagnetic/spin-chain/ferromagnetic phases as well as topological quantum phase transitions between gapped and gapless spin liquid phases.

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S. Mandal, Subhro Bhattacharjee, K. Sengupta, R. Shankar, G. Baskaran. 2011-01-07. Spin correlations and phase diagram of the perturbed Kitaev model. https://doi.org/10.1103/physrevb.84.155121

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