ANDERSON LOCALIZATION VERSUS DELOCALIZATION OF INTERACTING FERMIONS IN ONE-DIMENSION

Using the density matrix renormalization group algorithm, we investiga te the lattice model for spinless fermions in one dimension in the pre sence of a strong interaction and disorder. The phase sensitivity of t he ground state energy is determined with high accuracy for systems up to a size of 60 lattice constants. This quantity is found to be log n ormally distributed. The fluctuations grow algebraically with system s ize with a universal Exponent of approximate to 2/3 in the localized r egion of he phase diagram. Surprisingly we find, for an attractive int eraction, a delocalized phase of finite extension. The boundary of thi s delocalized phase is determined.