The Local Correlation Lengths in Ising Models with Free Surfaces
W. Korneta, Zdzisław Pytel
Abstract The nearest‐neighbor Ising model of a film is considered in which couplings between spins depend on the distances to the surfaces. The local correlation lengths in directions parallel and perpendicular to the surfaces of the model near different second‐order phase transitions are studied. The random‐phase approximation is used. Analytical expressions for the local correlation lengths are obtained. Assuming that one surface of the model of a film tends to infinity, local correlation lengths in the three‐dimensional semi‐infinite Ising model are obtained.
physica status solidi (b)•Apr 1, 1988•0 citations