BOUNDARY CRITICAL-BEHAVIOR OF 2-DIMENSIONAL RANDOM ISING-MODELS

Using Monte Carlo techniques and a star-triangle transformation, Ising models with random, 'strong' and 'weak', nearest-neighbour ferromagne tic couplings on a square lattice with a (1,1) surface are studied nea r the phase transition. Both surface and bulk critical properties are investigated. In particular, the critical exponents of the surface mag netization, beta(1), of the correlation length, nu, and of the critica l surface correlations, eta(parallel to), are analysed.