6533b850fe1ef96bd12a838f
RESEARCH PRODUCT
Ground state of the frustrated Hubbard model within DMFT: energetics of Mott insulator and metal from ePT and QMC
N. BlümerE. Kalinowskisubject
PhysicsCondensed Matter::Quantum GasesHubbard modelBethe latticeCondensed matter physicsStrongly Correlated Electrons (cond-mat.str-el)Quantum Monte CarloMott insulatorFOS: Physical sciencesCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsMott transitionCondensed Matter - Strongly Correlated ElectronsCondensed Matter::Strongly Correlated ElectronsElectrical and Electronic EngineeringGround stateCritical exponentLattice model (physics)description
We present a new method, ePT, for extrapolating few known coefficients of a perturbative expansion. Controlled by comparisons with numerically exact quantum Monte Carlo (QMC) results, 10th order strong-coupling perturbation theory (PT) for the Hubbard model on the Bethe lattice is reliably extrapolated to infinite order. Within dynamical mean-field theory (DMFT), we obtain continuous estimates of energy E and double occupancy D with unprecedented precision O(10^{-5}) for the Mott insulator above its stability edge U_{c1}=4.78 as well as critical exponents. In addition, we derive corresponding precise estimates for E and D in the metallic ground state from extensive low-temperature QMC simulations using a fit to weak-coupling PT while enforcing thermodynamic consistency.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2004-07-16 |