Particle-hole symmetry and the effect of disorder on the Mott-Hubbard insulator.
The understanding of the interplay of electron correlations and randomness in solids is enhanced by demonstrating that particle-hole ( p-h) 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 p-h symmetry is preserved, and shows the opposite behavior, i.e., conductivity increases with increasing disorder, when p-h symmetry is broken. The Mott insulating gap is insensitive to weak disorder when there is p-h symmetry, whereas in its absence the gap diminishes with increasing disorder.
Denteneer
P J
PJ
Lorentz Institute, Leiden University, P.O. Box 9506, 2300 RA Leiden, The Netherlands.
Scalettar
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Trivedi
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