title: Interband spectrum of weakly coupled stochastic lattice Ginzburg-Landau models.
abstract: We analyze the excitation spectrum of the generator associated with the relaxation rate to equilibrium in weakly coupled stochastic Ginzburg-Landau models on a spatial lattice Z(d). The spectrum has a quasiparticle interpretation. Depending on d and on the specific interaction, by solving the Bethe-Salpeter equation in the ladder approximation, we show the existence of a stable particle above the upper envelope of the two-particle band, possessing a concave dispersion curve. This result furthers our knowledge about the spectrum of the stochastic dynamics generator.
authors.affiliation: Departamento de Matemática, ICMC-USP, C.P. 668, 13560-970 São Carlos, SP, Brazil. veiga@icmc.sc.usp.br
authors.forename: Paulo A
authors.initials: PA
authors.lastname: Faria da Veiga
authors.forename: Michael
authors.initials: M
authors.lastname: O'Carroll
authors.forename: Ricardo
authors.initials: R
authors.lastname: Schor