Boson decay and the dynamical structure factor for the XXZ chain at finite magnetic field
arXiv:0705.3312 · doi:10.1016/j.physb.2007.10.304
Abstract
We study the longitudinal dynamical structure factor for the anisotropic spin-1/2 (XXZ) chain at finite magnetic field using bosonization. The leading irrelevant operators in the effective bosonic model stemming from band curvature describe boson decay processes and lead to a high-frequency tail and a finite width of the on-shell peak for . We use the Bethe ansatz to show that for and to calculate the amplitudes of the leading irrelevant operators in the effective field theory.
2 pages, 2 figures, proceedings SCES '07, Houston