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arXiv · 1201.3817

Dielectric breakdown in spin polarized Mott insulator

Zala Lenarčič·Peter Prelovšek
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Abstract

Nonlinear response of a Mott insulator to external electric field, corresponding to dielectric breakdown phenomenon, is studied within of a one-dimensional half-filled Hubbard model. It is shown that in the limit of nearly spin polarized insulator the decay rate of the ground state into excited holon-doublon pairs can be evaluated numerically as well to high accuracy analytically. Results show that the threshold field depends on the charge gap as $F_{th} \propto \Delta^{3/2}$. Numerical results on small systems indicate on the persistence of a similar mechanism for the breakdown for decreasing magnetization down to unpolarised system.

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Zala Lenarčič, Peter Prelovšek. 2012-01-18. Dielectric breakdown in spin polarized Mott insulator. https://doi.org/10.1103/physrevlett.108.196401

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