We study by the strong disorder renormalization group (RG) method the low-energy properties of the one-dimensional Hubbard model with random-hopping matrix-elements tmin <t< tmax, and with random onsite Coulomb repulsion terms 0≤ Umin <U< Umax. There are two critical phases, corresponding to an infinite randomness spin random singlet for strong interactions (Umin > tmax) and to an orbital infinite randomness fixed point for vanishing interactions (Umax tmax →0). To each critical infinite randomness fixed point is connected a Griffiths phase, the correlation length, and dynamical exponent of which have well defined asymptotic dependences on the corresponding quantum control parameter. The theoretical predictions for the scaling in the vicinity of the critical points compare well to numerical RG simulations.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Oct 11 2006|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics