The Mott-Anderson transition in the disordered one-dimensional Hubbard model

Ramesh V. Pai; Alexander Punnoose; Rudolf A. Römer

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The Mott-Anderson transition in the disordered one-dimensional Hubbard model

Ramesh V. Pai·Alexander Punnoose·Rudolf A. Römer

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Abstract

We use the density matrix renormalization group to study the quantum transitions that occur in the half-filled one-dimensional fermionic Hubbard model with onsite potential disorder. We find a transition from the gapped Mott phase with algebraic spin correlations to a gapless spin-disordered phase beyond a critical strength of the disorder $Δ_c \approx U/2$. Both the transitions in the charge and spin sectors are shown to be coincident. We also establish the finite-size corrections to the charge gap and the spin-spin correlation length in the presence of disorder and using a finite-size-scaling analysis we obtain the zero temperature phase diagram of the various quantum phase transitions that occur in the disorder-interaction plane.

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Ramesh V. Pai, Alexander Punnoose, Rudolf A. Römer. 1997-04-03. The Mott-Anderson transition in the disordered one-dimensional Hubbard model. https://arxiv.org/abs/cond-mat/9704027

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