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arXiv · 1403.4676

Hall conductance and topological invariant for open systems

H. Z. Shen·W. Wang·X. X. Yi
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Abstract

The Hall conductivity given by the Kubo formula is a linear response of the quantum transverse transport to a weak electric field. It has been intensively studied for a quantum system without decoherence, but it is barely explored for systems subject to decoherence. In this paper, we develop a formalism to deal with this issue for topological insulators. The Hall conductance for a topological insulator coupled to an environment is derived, the derivation is based on a linear response theory of open system. As an application, the Hall conductance of a two-band topological insulator and a two-dimensional lattice is presented and discussed.

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H. Z. Shen, W. Wang, X. X. Yi. 2014-10-07. Hall conductance and topological invariant for open systems. https://arxiv.org/abs/1403.4676

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