|
Matthew S. Foster and Andreas W. W. Ludwig
We study the combined effects of random hopping disorder and interparticle interactions in half filled Hubbard-like models of spinless fermions in two or more dimensions. In a given realization, the hopping disorder is chosen to break time-reversal invariance, but to preserve the special nesting symmetry responsible for the charge density wave instability of the clean, non-interacting Fermi surface. This disorder may arise, e.g., from the application of a random orbital magnetic field to the otherwise clean model. Using a perturbative renormalization group approach [1], we have identified a new, continuous metal-insulator transition in 2 + epsilon dimensions, stabilized by the presence of the interactions. [1] A. M. Finkelstein, Zh. Eksp. Teor. Fiz. 84, 168 (1983), Sov. Phys. JETP 57, 97 (1983). |
|