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arXiv · 0811.1380

A $Γ$-matrix generalization of the Kitaev model

Congjun Wu·Daniel Arovas·Hsiang-Hsuan Hung
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Abstract

We extend the Kitaev model defined for the Pauli-matrices to the Clifford algebra of $Γ$-matrices, taking the $4 \times 4$ representation as an example. On a decorated square lattice, the ground state spontaneously breaks time-reversal symmetry and exhibits a topological phase transition. The topologically non-trivial phase carries gapless chiral edge modes along the sample boundary. On the 3D diamond lattice, the ground states can exhibit gapless 3D Dirac cone-like excitations and gapped topological insulating states. Generalizations to even higher rank $Γ$-matrices are also discussed.

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Congjun Wu, Daniel Arovas, Hsiang-Hsuan Hung. 2009-04-11. A $Γ$-matrix generalization of the Kitaev model. https://doi.org/10.1103/physrevb.79.134427

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