Disorder and interaction in 2D: exact diagonalization study of the Anderson-Hubbard-Mott model.
We investigate, by numerically calculating the charge stiffness, the effects of random diagonal disorder and electron-electron interaction on the nature of the ground state in the 2D Hubbard model through the finite-size exact diagonalization technique. By comparing with the corresponding 1D Hubbard model results and by using heuristic arguments we conclude that it is unlikely that there is a 2D metal-insulator quantum phase transition, although the effect of interaction in some range of parameters is to substantially enhance the noninteracting charge stiffness.
Kotlyar
R
R
Naval Research Laboratory, Washington, DC 20375, USA. roza.kotlyar@intel.com
Das Sarma
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S