6533b7dafe1ef96bd126ed3a

RESEARCH PRODUCT

Quantum Monte Carlo study of insulating state in NaV2O5

H. AouragH. AouragSouraya Goumri-saidSouraya Goumri-said

subject

Condensed matter physicsHubbard modelChemistryMechanical EngineeringQuantum Monte CarloMonte Carlo methodMetals and AlloysSpectral densityGeneral MedicineState (functional analysis)Electronic structureMechanics of MaterialsPhase (matter)Materials ChemistryCoulombMoleculeCondensed Matter::Strongly Correlated ElectronsMetal–insulator transitionElectronic band structure

description

Abstract Quantum Monte Carlo (QMC) methods are being increasingly used as complements to Hartree–Fock (HF) methods for computing the electronic structure of molecules and materials. We investigate the nature of the insulating state driven by electronic correlations in the ladder compound NaV 2 O 5 ; considered as a quarter-filled system. We use an extended Hubbard model (EHM) to study the role of on-site and inter-site Coulomb interaction. It is found that the insulating state in the charge-disordered phase of this compound take origin from the transfer of spectral density and dynamical fluctuations. Our calculation allows us also, to understand the origin of the insulating states above T C and to estimate the relative importance of various physical mechanisms responsible for the gap formation.

https://doi.org/10.1016/s0925-8388(02)01367-1