Transition rates via Bethe ansatz for the spin-1/2 planar<i>XXZ</i>antiferromagnet

Abstract

A novel determinantal representation for matrix elements of local spin\noperators between Bethe wave functions of the one-dimensional s=1/2 XXZ model\nis used to calculate transition rates for dynamic spin structure factors in the\nplanar regime. In a first application, high-precision numerical data are\npresented for lineshapes and band edge singularities of the in-plane (xx)\ntwo-spinon dynamic spin structure factor.\n