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Density of states near the Mott-Hubbard transition in the limit of large dimensions

Stefan Kehrein
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Abstract

The zero temperature Mott-Hubbard transition as a function of the Coulomb repulsion U is investigated in the limit of large dimensions. The behavior of the density of states near the transition at U=U_c is analyzed in all orders of the skeleton expansion. It is shown that only two transition scenarios are consistent with the skeleton expansion for U<U_c: (i) The Mott-Hubbard transition is "discontinuous" in the sense that in the density of states finite spectral weight is redistributed at U_c. (ii) The transition occurs via a point at U=U_c where the system is neither a Fermi liquid nor an insulator.

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Stefan Kehrein. 1998-10-30. Density of states near the Mott-Hubbard transition in the limit of large dimensions. https://doi.org/10.1103/physrevlett.81.3912

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