title: Numerical solution of the t-J model with random exchange couplings in d=∞ dimensions.
abstract: To explore the nature of the metallic state near the transition to a Mott insulator, we investigate the t-J model with random exchange interaction in d=∞ dimensions. A numerically exact solution is obtained by an extension of the continuous-time quantum Monte Carlo method to the case of a vector bosonic field coupled to a local spin. We show that the paramagnetic solution near the Mott insulator describes an incoherent metal with a residual moment, and that single-particle excitations produce an additional band, which is separated from the Mott-Hubbard band.
authors.affiliation: Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, D-86135 Augsburg, Germany.
authors.forename: Junya
authors.initials: J
authors.lastname: Otsuki
authors.forename: Dieter
authors.initials: D
authors.lastname: Vollhardt