On the Soliton Dynamics of the Easy-Plane Antiferromagnetic Chain

Abstract

Soliton contributions to dynamical structure factors of the easy-plane antiferromagnetic chain in a symmetry breaking magnetic field are studied in the sine-Gordon approximation. By considering deviation from perfect antiparallel alignment of neighboring spins, it is shown that low-frequency peaks due to solitons appear around the ferromagnetic Bragg point. They may be observable by the neutron scattering experiment on TMMC.