CRITICAL-DYNAMICS OF THE XY-MODEL ON THE ONE-DIMENSIONAL SUPERLATTICEBY POSITION-SPACE RENORMALIZATION-GROUP

The critical dynamics of the isotropic XY-model on the one-dimensional superlattice is considered in the framework of the position space ren ormalization group theory. The decimation transformation is introduced by considering the equations of motion of the operators associated to the excitations of the system, and it corresponds to an extension of the procedure introduced by Stinchcombe and dos Santos (J. Phys. A18, L597 (1985)) for the homogeneous lattice. The dispersion relation is o btained exactly and the static and dynamic scaling forms are explicitl y determined. The dynamic critical exponent is also obtained and it is shown that it is identical to the one of the XY-model on the homogene ous chain.