We study the nature of metal-insulator transition in the paramagnetic state for the Hubbard model on the Bethe lattice. The single-particle density of states is calculated via the operator Lanczos method. Our study shows that the metal-insulator transition is continuous and there is no preformed gap. The quasiparticle weight vanishes linearly with the distance from the transition point ${(U}_c)$ in agreement with results of iterative perturbation theory and exact diagonalization method. Our $U_c$ is comparable to that by the random dispersion approximation. Our result indicates non-Fermi-liquid feature at the transition point.

• Received 8 August 2000

DOI:https://doi.org/10.1103/PhysRevB.62.12581