arXiv:cond-mat/9803149 · Physical Review Letters
Density of States near the Mott-Hubbard Transition in the Limit of Large Dimensions
Stefan K. Kehrein
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 ${U\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}U}_{c}$ 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 ${U\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}U}_{c}$ where the system is neither a Fermi liquid nor an insulator.