ON U(Q)[SU(2)]-SYMMETRICAL DRIVEN DIFFUSION

We study analytically a model where particles with hard-core repulsion diffuse on a finite one-dimensional lattice with space-dependent, asy mmetric hopping rates. The dynamics are given by the U(q)[SU(2)]-symme tric Hamiltonian of a generalized anisotropic Heisenberg ferromagnet. Exploiting this symmetry, we derive exact expressions for various corr elation functions. In the weakly driven system correlation length xi(s ) and correlation time xi(t) are related by xi(t) - xi(s)2 indicating a dynamical exponent z = 2 as for symmetric diffusion. But also in str ongly driven systems with finite density we find correlation functions with a dynamical exponent z = 2. This is not expected from the finite -size scaling analysis of the model.