Complex phase ordering of the one-dimensional Heisenberg model with conserved order parameter

We study the phase-ordering kinetics of the one-dimensional Heisenberg model with conserved order parameter by means of scaling arguments and numerical simulations. We find a rich dynamical pattern with a regime characterized by two distinct growing lengths. Spins are found to be coplanar over regions of a typical size L(V)(t), while inside these regions smooth rotations associated to a smaller length L(C)(t) are observed. Two different and coexisting ordering mechanisms are associated to these lengths, leading to different growth laws L(V)(t)similar to t(1/3) and L(C)(t)similar to t(1/4) violating dynamical scaling.