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arXiv · 1604.08138

Dual-fermion approach to the Anderson-Hubbard model

P. Haase·S. -X. Yang·T. Pruschke·J. Moreno·M. Jarrell
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Abstract

We apply the recently developed dual fermion algorithm for disordered interacting systems to the Anderson-Hubbard model. This algorithm is compared with dynamical cluster approximation calculations for a one-dimensional system to establish the quality of the approximation in comparison with an established cluster method. We continue with a three-dimensional (3d) system and look at the antiferromagnetic, Mott and Anderson localization transitions. The dual fermion approach leads to quantitative as well as qualitative improvement of the dynamical mean-field results and it allows one to calculate the hysteresis in the double occupancy in 3d taking into account nonlocal correlations.

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P. Haase, S. -X. Yang, T. Pruschke, J. Moreno, M. Jarrell. 2016-04-27. Dual-fermion approach to the Anderson-Hubbard model. https://doi.org/10.1103/physrevb.95.045130

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