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arXiv · 1108.6057

Signatures of Delocalization in the Fermionic 1D Hubbard Model with Box Disorder: Comparative Study with DMRG and R-DMFT

Julia Wernsdorfer·Georg Harder·Ulrich Schollwoeck·Walter Hofstetter
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Abstract

We investigate the 1D Anderson-Hubbard model at half filling with box-disorder. The ground state phase diagram is obtained by means of real-space dynamical mean-field theory (R-DMFT) and the density matrix renormalization group (DMRG). We find Mott insulating and Anderson localized regimes as well as a strong indication of a delocalized phase for intermediate interaction and disorder strength within accessible system sizes. These phases are characterized and distinguished by qualitatively different scaling behavior of the local density of states, the energy gap in the excitation spectrum and the inverse participation number.

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Julia Wernsdorfer, Georg Harder, Ulrich Schollwoeck, Walter Hofstetter. 2011-08-30. Signatures of Delocalization in the Fermionic 1D Hubbard Model with Box Disorder: Comparative Study with DMRG and R-DMFT. https://arxiv.org/abs/1108.6057

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