Surface metal-insulator transition in the Hubbard model

TL;DR

This paper investigates the surface metal-insulator transition in the Hubbard model using dynamical mean-field theory, revealing a critical interaction strength and surface-confined excitations dependent on geometry and wave vector.

Contribution

It provides a detailed analysis of the surface Mott transition in the Hubbard model, highlighting the role of surface geometry and wave vector in the transition and surface excitations.

Findings

Transition occurs at a unique critical interaction strength.

Surface excitations can be confined to two dimensions.

Surface geometry influences the electronic spectrum.

Abstract

The correlation-driven metal-insulator (Mott) transition at a solid surface is studied within the Hubbard 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.