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arXiv · 1511.06822

Charge dynamics in doped Mott insulators on a honeycomb lattice

Xixiao Ma·Yu Lan·Ling Qin·Shiping Feng
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Abstract

Within the framework of the fermion-spin theory, the charge transport in the doped Mott insulators on a honeycomb lattice is studied by taking into account the pseudogap effect. It is shown that the conductivity spectrum in the low-doped regime is separated by the pseudogap into a low-energy non-Drude peak followed by a broad midinfrared band. However, the decrease of the pseudogap with the increase of doping leads to a shift of the position of the midinfrared band towards to the low-energy non-Drude peak, and then the low-energy Drude behavior recovers in the high-doped regime. The combined results of both the doped honeycomb-lattice and square-lattice Mott insulators indicate that the two-component conductivity induced by the pseudogap is a universal feature in the doped Mott insulators.

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Xixiao Ma, Yu Lan, Ling Qin, Shiping Feng. 2015-11-21. Charge dynamics in doped Mott insulators on a honeycomb lattice. https://doi.org/10.1142/s0217984916501074

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