Non-equilibrium phase transitions in lattice systems with random-field competing kinetics: mean-field theory

AbslracL The study by kinetic mean-field techniques of a ddimensional king system characterized by a sort of dpomicol &order reveals a rich phase diagram which exhibils a non-equilibrium lricnlical paint (only) for d > 2, and re-entrance phenomena. The system time evolution is stochastic due to the simultaneous action of wera l independent spin-flip mechanisms, each cot’responding to a different applied magnetic field. Such competition brings a b u t randomness and a type of frustralion that may occur also in real systems. I n fad, this models the actual case of a magnetic system under a very rapidly fluctuating field, for example. Funhermore, the system may be interpreted as a non-equilibrium random-field system which. unlike the familiar quenched and annealed cases, contains a fast random dillusion of disorder.