| Kitaev model was invented to illustrate certain key ideas in topological quantum computation. However, the model has become very interesting on its own right as a frustrated quantum spin model exhibiting a quantum spin liquid behvaior with a definrich spectrum. We will arrive at Kitaevs exact results using RVB mean field theory and gauge theory techniques. This will establish a connection of Kitaev's Majorana fermion construction to the RVB SU(2) slave boson theory used for 2D Heisenberg antiferromagnet. We will elaborate on the nature of spin correlations in Kitaev model and bring out a generalised `valence bond' involving triplets. We will also show an exact solution of a Kitaev model defined on a particular 2 dimensional model, which exhibits even a closer connection to RVB spin liquids. Nature of topological excitations in Kitaev model and RVB models will be contrasted. |
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