Publication: Variational Monte Carlo study of Anderson localization in the Hubbard model

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Title	Variational Monte Carlo study of Anderson localization in the Hubbard model
Authors/Editors*	A. Farhoodfar, R. J. Gooding, and W. A. Atkinson
Where published*	Phys. Rev. B
How published*	Journal
Year*	2011
Volume	84
Number
Pages	205125
Publisher
Keywords
Link	http://prb.aps.org/abstract/PRB/v84/i20/e205125
Abstract	We have studied the effects of interactions on persistent currents in half-filled and quarter-filled Hubbard models with weak and intermediate strength disorder. Calculations are performed using a variational Gutzwiller ansatz that describes short-range correlations near the Mott transition. We apply an Aharonov-Bohm magnetic flux, which generates a persistent current that can be related to the Thouless conductance. The magnitude of the current depends on both the strength of the screened disorder potential and the strength of electron-electron correlations, and the Anderson localization length can be extracted from the scaling of the current with system size. At half-filling, the persistent current is reduced by strong correlations when the interaction strength is large. Surprisingly, we find that the disorder potential is strongly screened in the large interaction limit, so that the localization length grows with increasing interaction strength even as the magnitude of the current is suppressed. This supports earlier dynamical mean-field-theory predictions that the elastic scattering rate is suppressed near the Mott transition.