Effects of Dzyaloshinskii-Moriya Interaction in the Dynamics of s = 1/2 XX Chain

Abstract

We consider the s = 1/2 transverse XX chain with the Dzyaloshinskii-Moriya (DM) interaction directed along z-axis in spin space to examine the effects of the DM interaction on the zz, xx (yy) and xy (yx) dynamic structure factors. With the help of a unitary transformation, the DM interaction can be eliminated resulting in a renormalized isotropic (XX) exchange interaction. The zz dynamic structure factor remains the same as for the chain without the DM interaction but with the renormalized XX interaction; for this reason, zz dynamics cannot be used in measuring the DM interaction constant. On the contrary, the xx (yy) and xy (yx) dynamic structure factors exhibit drastical changes permitting to extract the DM interaction constant by corresponding dynamic measurements.