English
Related papers

Related papers: The Hubbard Dimer: A density functional case study…

200 papers

We describe how density-functional theory, well-known for its many uses in ab initio calculations of electronic structure, can be used to study the ground state of inhomogeneous model Hamiltonians. The basic ideas and concepts are discussed…

Materials Science · Physics 2007-05-23 Valter L. Libero , Klaus Capelle

A reformulation of site-occupation embedding theory (SOET) in terms of Green's functions is presented. Referred to as site-occupation--Green's function embedding theory (SOGET), this novel extension of density-functional theory for model…

Strongly Correlated Electrons · Physics 2019-11-07 Laurent Mazouin , Matthieu Saubanère , Emmanuel Fromager

We propose a general variational fermionic many-body wavefunction that generates an effective Hamiltonian in a quadratic form, which can then be exactly solved. The theory can be constructed within the density functional theory framework,…

Strongly Correlated Electrons · Physics 2020-10-30 Xindong Wang , Xiao Chen , Liqin Ke , Hai-Ping Cheng , B. N. Harmon

Open many-body quantum systems have attracted renewed interest in the context of quantum information science and quantum transport with biological clusters and ultracold atomic gases. The physical relevance in many-particle bosonic systems…

Quantum Gases · Physics 2015-10-02 G. Kordas , D. Witthaut , P. Buonsante , A. Vezzani , R. Burioni , A. I. Karanikas , S. Wimberger

A variational formulation for the calculation of interacting fermion systems based on the density-matrix functional theory is presented. Our formalism provides for a natural integration of explicit many-particle effects into standard…

Strongly Correlated Electrons · Physics 2013-05-29 Peter E. Bloechl , Christian F. J. Walther , Thomas Pruschke

The recently developed hypercomplex Kohn-Sham (HCKS) theory shows great potential to overcome the static/strong correlation issue in density functional theory (DFT), which highlights the necessity of further exploration of the HCKS theory…

Chemical Physics · Physics 2022-03-16 Neil Qiang Su

As density functional theory conventionally assumes that the density of a chosen model system (e.g., the Kohn-Sham system) is the same as the exact one, one might expect that approximations to the exact density introduce supplementary…

Chemical Physics · Physics 2009-02-17 A. Savin

The locality hypothesis in density-functional theory (DFT) states that the functional derivative of the Hohenberg-Kohn universal functional can be expressed as a local multiplicative potential function, and this is the basis of DFT and of…

Atomic Physics · Physics 2007-05-23 Ingvar Lindgren , Sten Salomonson

Over the years, several schemes have been proposed to describe multireference systems with Kohn-Sham Density Functional Theory. Problematic is the combination of two aspects: the Kohn-Sham reference wavefunction is usually taken to be a…

Strongly Correlated Electrons · Physics 2019-08-01 Pablo Ramos , Michele Pavanello

This article is part-I of a review of density-functional theory (DFT) that is the most widely used method for calculating electronic structure of materials. The accuracy and ease of numerical implementation of DFT methods has resulted in…

Materials Science · Physics 2023-05-25 Prashant Singh , Manoj K Harbola

The central quantity of density functional theory is the so-called exchange-correlation functional. This quantity encompasses all non-trivial many-body effects of the ground-state and has to be approximated in any practical application of…

Materials Science · Physics 2012-06-29 Miguel A. L. Marques , Micael J. T. Oliveira , Tobias Burnus

We evaluate the density matrix of an arbitrary quantum mechanical system in terms of the quantities pertinent to the solution of the time-dependent density functional theory (TDDFT) problem. Our theory utilizes the adiabatic connection…

Mesoscale and Nanoscale Physics · Physics 2019-09-04 Vladimir U. Nazarov

Self-consistent-field (SCF) approximations formulated using Hartree-Fock (HF) or Kohn-Sham Density Functional Theory (KS-DFT) both have the potential to yield multiple solutions. However, the formal relationship between multiple solutions…

Chemical Physics · Physics 2021-01-06 Rhiannon A. Zarotiadis , Hugh G. A. Burton , Alex J. W. Thom

Exotic phases of matter can emerge from strong correlations in quantum many-body systems. Quantum gas microscopy affords the opportunity to study these correlations with unprecedented detail. Here we report site-resolved observations of…

In quantum simulation, many-body phenomena are probed in controllable quantum systems. Recently, simulation of Bose-Hubbard Hamiltonians using cold atoms revealed previously hidden local correlations. However, fermionic many-body Hubbard…

Mesoscale and Nanoscale Physics · Physics 2016-04-26 J. Salfi , J. A. Mol , R. Rahman , G. Klimeck , M. Y. Simmons , L. C. L. Hollenberg , S. Rogge

A recent work [arXiv:2401.04685] has merged $N$-centered ensembles of neutral and charged electronic ground states with ensembles of neutral ground and excited states, thus providing a general and in-principle exact (so-called extended…

Strongly Correlated Electrons · Physics 2024-05-14 Filip Cernatic , Emmanuel Fromager

Forty-five years after the point de d\'epart [1] of density functional theory, its applications in chemistry and the study of electronic structures keep steadily growing. However, the precise form of the energy functional in terms of the…

Chemical Physics · Physics 2019-10-29 Philippe Blanchard , José M. Gracia-Bondía , Joseph C. Várilly

Predictivity of the Kohn-Sham approach to dynamical problems, when regarded as an initial value problem in a time-dependent density functional framework, is analysed for a class of models for which the argument devised in the work of Maitra…

Other Condensed Matter · Physics 2015-06-16 Walter Tarantino

We study both static and transport properties of model quantum dots, employing density functional theory as well as (numerically) exact methods. For the lattice model under consideration the accuracy of the local-density approximation…

Mesoscale and Nanoscale Physics · Physics 2011-04-11 S. Schenk , P. Schwab , M. Dzierzawa , U. Eckern

The asymmetric Hubbard model is used in investigating the lattice gas of the moving particles of two types. The model is considered within the dynamical mean-field method. The effective single-site problem is formulated in terms of the…

Strongly Correlated Electrons · Physics 2024-01-30 I. V. Stasyuk , O. B. Hera
‹ Prev 1 4 5 6 7 8 10 Next ›