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arXiv · 1510.05456

A Novel Insulator by Holographic Q-lattices

Yi Ling·Peng Liu·Jian-Pin Wu
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Abstract

We construct a bulk geometry with Q-lattice structure, which is implemented by two gauge fields and a coupling between the lattice and the Maxwell field. This gravity dual model can describe a novel insulator which exhibits some key features analogous to Mott insulator. In particular, a hard gap in insulating phase as well as vanishing DC conductivity can be simultaneously achieved. In addition, we discuss the non-Drude behavior of the optical conductivity in low frequency region in insulating phase, which exhibits some novel characteristics different from ordinary Mott insulator.

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Yi Ling, Peng Liu, Jian-Pin Wu. 2016-02-19. A Novel Insulator by Holographic Q-lattices. https://doi.org/10.1007/jhep02(2016)075

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