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arXiv · 1212.4022

Numerical solution of the t-J model with random exchange couplings in d=infinity dimensions

Junya Otsuki·Dieter Vollhardt
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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=infinity dimensions. A numerically exact solution is obtained by an extension of the continuous-time quantum Monte Carlo (CT-QMC) 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.

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Junya Otsuki, Dieter Vollhardt. 2012-12-17. Numerical solution of the t-J model with random exchange couplings in d=infinity dimensions. https://doi.org/10.1103/physrevlett.110.196407

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