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Register a new userQuantum Monte Carlo Study of an Interaction-Driven Band Insulator to Metal Transition
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Richard T. Scalettar
Publication date
2006
fields
Physics
and research's language is
English
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We study the transitions from band insulator to metal to Mott insulator in the ionic Hubbard model on a two dimensional square lattice using determinant Quantum Monte Carlo. Evaluation of the temperature dependence of the conductivity demonstrates that the metallic region extends for a finite range of interaction values. The Mott phase at strong coupling is accompanied by antiferromagnetic (AF) order. Inclusion of these intersite correlations changes the phase diagram qualitatively compared to dynamical mean field theory.
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