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arXiv · 1412.8644

Mott insulator breakdown through pattern formation

Pedro Ribeiro·Andrey E. Antipov·Alexey N. Rubtsov
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Abstract

We study the breakdown of a Mott insulator with the thermodynamic imbalance induced by an applied bias voltage. By analyzing the instabilities of the magnetic susceptibility, we describe a rich non-equilibrium phase diagram, obtained for different applied voltages, that exhibits phases with a spatially patterned charge gap. For a finite voltage, smaller than the value of the equilibrium Mott gap, the formation of patterns coincides with the emergence of mid-gap states contributing to a finite steady-state conductance. We discuss the experimental implications of this new scenario of Mott breakdown.

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Pedro Ribeiro, Andrey E. Antipov, Alexey N. Rubtsov. 2014-12-30. Mott insulator breakdown through pattern formation. https://doi.org/10.1103/physrevb.93.144305

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