N ov 1 99 8 Surface metal - insulator transition in the Hubbard model
نویسندگان
چکیده
The correlation-driven metal-insulator (Mott) transition at a solid surface is studied within the Hub-bard model for a semi-infinite lattice by means of the dynamical mean-field theory. The transition takes place at a unique critical strength of the interaction. Depending on the surface geometry, the interaction strength and the wave vector, we find one-electron excitations in the coherent part of the surface-projected metallic spectrum which are confined to two dimensions.
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