title: Dielectric breakdown in spin-polarized Mott insulator.
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 pair can be evaluated numerically as well to high accuracy analytically. Results show that the threshold field depends on the charge gap as F(th)∝Δ(3/2). Numerical results on small systems indicate on the persistence of a similar mechanism for the breakdown for decreasing magnetization down to unpolarized system.
authors.affiliation: J. Stefan Institute, SI-1000 Ljubljana, Slovenia.
authors.forename: Zala
authors.initials: Z
authors.lastname: Lenarčič
authors.forename: Peter
authors.initials: P
authors.lastname: Prelovšek