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The interplay between topological insulators and Mott physics has attracted a growing attention with possible relevance to iridate physics [1-3]. Here, we investigate the interplay between spin-orbit coupling and Mott physics [4] through an anisotropic tight-binding model on the honeycomb lattice [5]. The phase diagram contains a quantum spin Hall phase until moderate interactions as well as two magnetic ordered phases, a Neel phase and a Spiral ordered phase, at large interactions [4]. Applying the slave-rotor technique and considering gauge fluctuations, we describe the formation of spin texture above the Mott transition. In the quantum Spin Hall phase with anisotropic coupling, the Z2 topological invariant relates to transport of the helical edge states. We discuss possible applications to thin films of Na2IrO3 [6]. Doping these systems might lead to unconventional superconductivity [7].
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