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Title: Band insulator to Mott insulator transition in a bilayer Hubbard model

Abstract

The ground state phase diagram of the half-filled repulsive Hubbard model in a bilayer is investigated using cluster dynamical mean field theory. For weak to intermediate values of Coulomb repulsion U, the system undergoes a transition from a Mott insulating phase to a metallic phase and then onto a band insulating phase as the interlayer hopping is increased. In the strong coupling case, the model exhibits a direct crossover from a Mott insulating phase to a band insulating phase. These results are robust with respect to the presence or absence of magnetic order.

Authors:
 [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
936534
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 75; Journal Issue: 19
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COULOMB FIELD; GROUND STATES; HUBBARD MODEL; PHASE DIAGRAMS; PHASE TRANSFORMATIONS; ELECTRICAL INSULATORS

Citation Formats

Kancharla, Srivenkateswara S, and Okamoto, Satoshi. Band insulator to Mott insulator transition in a bilayer Hubbard model. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.75.193103.
Kancharla, Srivenkateswara S, & Okamoto, Satoshi. Band insulator to Mott insulator transition in a bilayer Hubbard model. United States. doi:10.1103/PhysRevB.75.193103.
Kancharla, Srivenkateswara S, and Okamoto, Satoshi. Mon . "Band insulator to Mott insulator transition in a bilayer Hubbard model". United States. doi:10.1103/PhysRevB.75.193103.
@article{osti_936534,
title = {Band insulator to Mott insulator transition in a bilayer Hubbard model},
author = {Kancharla, Srivenkateswara S and Okamoto, Satoshi},
abstractNote = {The ground state phase diagram of the half-filled repulsive Hubbard model in a bilayer is investigated using cluster dynamical mean field theory. For weak to intermediate values of Coulomb repulsion U, the system undergoes a transition from a Mott insulating phase to a metallic phase and then onto a band insulating phase as the interlayer hopping is increased. In the strong coupling case, the model exhibits a direct crossover from a Mott insulating phase to a band insulating phase. These results are robust with respect to the presence or absence of magnetic order.},
doi = {10.1103/PhysRevB.75.193103},
journal = {Physical Review B},
number = 19,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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