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Anderson-localization versus delocalization of interacting fermions in one dimension

P. Schmitteckert·T. Schulze·C. Schuster·P. Schwab·U. Eckern
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Abstract

Using the density matrix renormalization group algorithm, we investigate the lattice model for spinless fermions in one dimension in the presence of a strong interaction and disorder. The phase sensitivity of the ground state energy is determined with high accuracy for systems up to a size of 60 lattice constants. This quantity is found to be log-normally distributed. The fluctuations grow algebraically with system size with a universal exponent of ~2/3 in the localized region of the phase diagram. Surprizingly, we find, for an attractive interaction, a delocalized phase of finite extension. The boundary of this delocalized phase is determined.

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P. Schmitteckert, T. Schulze, C. Schuster, P. Schwab, U. Eckern. 1997-06-11. Anderson-localization versus delocalization of interacting fermions in one dimension. https://doi.org/10.1103/physrevlett.80.560

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