title: Doublon relaxation in the Bose-Hubbard model.
abstract: The decay of a high-energy double occupancy state, doublon, in a narrow-band lattice requires the creation of a coherent many-particle excitation. This leads to an exponentially long relaxation time of such a state. We show that, if the average occupation number is sufficiently small, the corresponding exponent may be evaluated exactly. To this end we develop the quasiclassical approach to calculation of the high-order tree-level decay amplitudes.
authors.affiliation: I. Institut für Theoretische Physik, Universität Hamburg, Hamburg, Germany.
authors.forename: A L
authors.initials: AL
authors.lastname: Chudnovskiy
authors.forename: D M
authors.initials: DM
authors.lastname: Gangardt
authors.forename: A
authors.initials: A
authors.lastname: Kamenev