Pseudo-one-dimensional kinetic Ising model

A simple kinetic model of the weakly coupled linear Ising chains is treated. The →q-dependent dynamical susceptibility is obtained, introducing the interchain molecular field into exact one-dimensional solutions. The usual molecular-field-type critical slowing down as T→Tc is accompanied by an additional noncritical, highly anisotropic slowing down due to high-intrachain short-range order. For the →q=0 mode the factor of the one-dimensional slowing down goes with decreasing temperature as the square of the one-dimensional correlation length. In the case of a strong anisotropy (J_∥J_⊥), this factor surpasses the value of the ratio J_∥J_⊥ already well above Tc.