UNIVERSALITY CLASS IN THE ONE-DIMENSIONAL LOCALIZATION PROBLEM

Weak disorder behavior of the Lyapunov exponent is investigated for a one-dimensional disordered system whose band structure and transfer ma trix form are manifestly different from the standard ones encountered in tight-binding models, For diagonal disorder, the critical exponents governing the divergence of the localization length at zero disorder are identical with those predicted for tight-binding models. For off-d iagonal disorder, a new exponent is found in one of the band edges, in dicating a different universality class. The scaling functions near th e different band edges are displayed, and their values for zero argume nts are not identical at all edges.