RANDOM-BOND ISING CHAIN IN A TRANSVERSE MAGNETIC-FIELD - A FINITE-SIZE-SCALING ANALYSIS

We investigate the zero-temperature quantum phase transition of the ra ndom-bond Ising chain in a transverse magnetic field. Its critical pro perties are identical to those of the McCoy-Wu model, which is a class ical Ising model in two dimensions with layered disorder. The latter i s studied via Monte Carlo simulations and transfer matrix calculations and the critical exponents are determined with a finite-size scaling analysis. The magnetization and susceptibility obey conventional rathe r than activated scaling. We observe that the order parameter and corr elation function probability distribution show a nontrivial scaling ne ar the critical point, which implies a hierachy of critical exponents associated with the critical behavior of the generalized correlation l engths.