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Particle-Hole Symmetry and the Effect of Disorder on the Mott-Hubbard Insulator

P. J. H. Denteneer·R. T. Scalettar·N. Trivedi
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Abstract

Recent experiments have emphasized that our understanding of the interplay of electron correlations and randomness in solids is still incomplete. We address this important issue and demonstrate that particle-hole (ph) symmetry plays a crucial role in determining the effects of disorder on the transport and thermodynamic properties of the half-filled Hubbard Hamiltonian. We show that the low-temperature conductivity decreases with increasing disorder when ph-symmetry is preserved, and shows the opposite behavior, i.e. conductivity increases with increasing disorder, when ph-symmetry is broken. The Mott insulating gap is insensitive to weak disorder when there is ph-symmetry, whereas in its absence the gap diminishes with increasing disorder.

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P. J. H. Denteneer, R. T. Scalettar, N. Trivedi. 2001-06-11. Particle-Hole Symmetry and the Effect of Disorder on the Mott-Hubbard Insulator. https://doi.org/10.1103/physrevlett.87.146401

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