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arXiv · 1309.2887

Charge avalanches and depinning in the Coulomb glass: The role of long-range interactions

Juan Carlos Andresen·Yohanes Pramudya·Helmut G. Katzgraber·Creighton K. Thomas·Gergely T. Zimanyi·V. Dobrosavljevic
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Abstract

We explore the stability of far-from-equilibrium metastable states of a three-dimensional Coulomb glass at zero temperature by studying charge avalanches triggered by a slowly varying external electric field. Surprisingly, we identify a sharply defined dynamical ("depinning") phase transition from stationary to nonstationary charge displacement at a critical value of the external electric field. Using particle-conserving dynamics, scale-free system-spanning avalanches are observed only at the critical field. We show that the qualitative features of this depinning transition are completely different for an equivalent short-range model, highlighting the key importance of long-range interactions for nonequilibrium dynamics of Coulomb glasses.

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Juan Carlos Andresen, Yohanes Pramudya, Helmut G. Katzgraber, Creighton K. Thomas, Gergely T. Zimanyi, V. Dobrosavljevic. 2016-03-24. Charge avalanches and depinning in the Coulomb glass: The role of long-range interactions. https://doi.org/10.1103/physrevb.93.094429

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