Pairing Interaction in the twodimensional Hubbard model studied with a dynamic cluster quantum Monte Carlo approximation
Abstract
A dynamic cluster quantum Monte Carlo approximation is used to study the effective pairing interaction of a 2D Hubbard model with a near neighbor hopping $t$ and an onsite Coulomb interaction $U$ . The effective pairing interaction is characterized in terms of the momentum and frequency dependence of the eigenfunction of the leading eigenvalue of the irreducible particleparticle vertex. The momentum dependence of this eigenfunction is found to vary as $$(\cos k_x\cos k_y)$$ over most of the Brillouin zone and its frequency dependence is determined by the $S=1$ particlehole continuum which for large $U$ varies as several times $J$. This implies that the effective pairing interaction is attractive for singlets formed between nearneighbor sites and retarded on a time scale set by $$(2J)^{1}$$. The strength of the pairing interaction measured by the size of the dwave eigenvalue peaks for $U$ of order the bandwidth $8t$. It is found to increase as the system is underdoped.
 Authors:
 ORNL
 University of Cincinnati
 University of California, Santa Barbara
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Nanophase Materials Sciences; Center for Computational Sciences
 Sponsoring Org.:
 USDOE Office of Science (SC)
 OSTI Identifier:
 1003569
 DOE Contract Number:
 DEAC0500OR22725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review B; Journal Volume: 74; Journal Issue: 9
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; APPROXIMATIONS; BRILLOUIN ZONES; EIGENFUNCTIONS; EIGENVALUES; FREQUENCY DEPENDENCE; HUBBARD MODEL; PAIRING INTERACTIONS
Citation Formats
Maier, Thomas A, Jarrell, Mark, and Scalapino, Douglas. Pairing Interaction in the twodimensional Hubbard model studied with a dynamic cluster quantum Monte Carlo approximation. United States: N. p., 2006.
Web. doi:10.1103/PhysRevB.74.094513.
Maier, Thomas A, Jarrell, Mark, & Scalapino, Douglas. Pairing Interaction in the twodimensional Hubbard model studied with a dynamic cluster quantum Monte Carlo approximation. United States. doi:10.1103/PhysRevB.74.094513.
Maier, Thomas A, Jarrell, Mark, and Scalapino, Douglas. Sun .
"Pairing Interaction in the twodimensional Hubbard model studied with a dynamic cluster quantum Monte Carlo approximation". United States.
doi:10.1103/PhysRevB.74.094513.
@article{osti_1003569,
title = {Pairing Interaction in the twodimensional Hubbard model studied with a dynamic cluster quantum Monte Carlo approximation},
author = {Maier, Thomas A and Jarrell, Mark and Scalapino, Douglas},
abstractNote = {A dynamic cluster quantum Monte Carlo approximation is used to study the effective pairing interaction of a 2D Hubbard model with a near neighbor hopping $t$ and an onsite Coulomb interaction $U$ . The effective pairing interaction is characterized in terms of the momentum and frequency dependence of the eigenfunction of the leading eigenvalue of the irreducible particleparticle vertex. The momentum dependence of this eigenfunction is found to vary as $(\cos k_x\cos k_y)$ over most of the Brillouin zone and its frequency dependence is determined by the $S=1$ particlehole continuum which for large $U$ varies as several times $J$. This implies that the effective pairing interaction is attractive for singlets formed between nearneighbor sites and retarded on a time scale set by $(2J)^{1}$. The strength of the pairing interaction measured by the size of the dwave eigenvalue peaks for $U$ of order the bandwidth $8t$. It is found to increase as the system is underdoped.},
doi = {10.1103/PhysRevB.74.094513},
journal = {Physical Review B},
number = 9,
volume = 74,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

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