Correlated Insulated Phase Suggests Bond Order between Band and Mott Insulators in Two Dimensions
Abstract
We investigate the ground state phase diagram of the halffilled repulsive Hubbard model in two dimensions in the presence of a staggered potential ?, the socalled ionic Hubbard model, using cluster dynamical mean field theory. We find that for large Coulomb repulsion, U , the system is a Mott insulator (MI). For weak to intermediate values of ?, on decreasing U, the Mott gap closes at a critical value Uc1(?) beyond which a correlated insulating phase with possible bond order (BO) is found. Further, this phase undergoes a firstorder transition to a band insulator (BI) at Uc2(?) with a finite charge gap at the transition. For large ?, there is a direct firstorder transition from a MI to a BI with a single metallic point at the phase boundary
 Authors:
 ORNL
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC)
 OSTI Identifier:
 930843
 DOE Contract Number:
 DEAC0500OR22725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review Letters; Journal Volume: 98
 Country of Publication:
 United States
 Language:
 English
 Subject:
 36 MATERIALS SCIENCE; COULOMB FIELD; GROUND STATES; HUBBARD MODEL; MEANFIELD THEORY; PHASE DIAGRAMS; ELECTRICAL INSULATORS; ENERGY GAP; PHASE TRANSFORMATIONS; Mott Insulators
Citation Formats
Kancharla, Srivenkateswara S, and Dagotto, Elbio R. Correlated Insulated Phase Suggests Bond Order between Band and Mott Insulators in Two Dimensions. United States: N. p., 2007.
Web. doi:10.1103/PhysRevLett.98.016402.
Kancharla, Srivenkateswara S, & Dagotto, Elbio R. Correlated Insulated Phase Suggests Bond Order between Band and Mott Insulators in Two Dimensions. United States. doi:10.1103/PhysRevLett.98.016402.
Kancharla, Srivenkateswara S, and Dagotto, Elbio R. Mon .
"Correlated Insulated Phase Suggests Bond Order between Band and Mott Insulators in Two Dimensions". United States.
doi:10.1103/PhysRevLett.98.016402.
@article{osti_930843,
title = {Correlated Insulated Phase Suggests Bond Order between Band and Mott Insulators in Two Dimensions},
author = {Kancharla, Srivenkateswara S and Dagotto, Elbio R},
abstractNote = {We investigate the ground state phase diagram of the halffilled repulsive Hubbard model in two dimensions in the presence of a staggered potential ?, the socalled ionic Hubbard model, using cluster dynamical mean field theory. We find that for large Coulomb repulsion, U , the system is a Mott insulator (MI). For weak to intermediate values of ?, on decreasing U, the Mott gap closes at a critical value Uc1(?) beyond which a correlated insulating phase with possible bond order (BO) is found. Further, this phase undergoes a firstorder transition to a band insulator (BI) at Uc2(?) with a finite charge gap at the transition. For large ?, there is a direct firstorder transition from a MI to a BI with a single metallic point at the phase boundary},
doi = {10.1103/PhysRevLett.98.016402},
journal = {Physical Review Letters},
number = ,
volume = 98,
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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