Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)

A New Efficient Method in Calculation of the Ground State and Few Excited States of Hubbard Chain Nanostructures

Faizabadi Edris, M. Solaimani, Khayatzadeh Mohammad Reza

Published Sep 1, 2006• 0 citations
Publisher

Abstract

A new method for calculation of the ground state of the Hubbard Hamiltonian is presented. With the same procedure by using induction and computer simulation we developed this method to higher atom and electron number.
DOI
10.1109/icimw.2006.368668

Related papers

New formalism in evaluation of the ground and few excited states of Hubbard chain nanostructures

Edris Faizabadi, Maryam Soleimani

A new, simple and efficient method is presented for calculation of the ground and a few excited states of Hubbard chain nanostructures. By using this method, the photoemission spectral function for organic charge transfer salt TTF-TCNQ, is calculated. For a chain with maximum 70 sites the result is in good agreement with the previous works but there is a difference for further number of sites in the chain, which is discussed in the text with all the specifics. We also show that a source of errors in density matrix renormalization group method for a one dimensional chain is the deficiency of the matrix product scheme for generating the desired states of the linear chain.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Nov 15, 2007•0 citations

Evaluation of the spectral function for the chain nanostructures TTF-TCNQ

Edris Faizabadi, Maryam Soleimani

The photoemission spectral function for organic charge transfer salt TTF-TCNQ is calculated with a new, simple and efficient method. This method is presented for calculation of the ground and a few excited states of Hubbard chain nanostructures.

International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)•Sep 1, 2007•0 citations

Exact Diagonalization of Many-Fermion Hamiltonian Combined with Wave-Function Readjustment II. Metallicity and Electron Localization in Nanoscopic Systems

Józef Spałek, Adam Rycerz, W. Wójcik

We apply our new method of approach to electronic states in correlated systems [for a brief review, Part I, see: Acta Phys. Pol. B31, 2879 (2000)] to the analysis of the states and electron localization in nanoscopic chains containing up to N = 12 atoms. The Mott and the Hubbard criteria of localization are explicitly evaluated and the importance of the former is stressed. We also define the many-particle wave function and calculate it explicitly for the hydrogen molecule. Further applications of our method are listed at the end.

Acta Physica Polonica B•Oct 1, 2001•2 citations

Quantum Monte Carlo Calculations for the Ground State of the Three-Band Hubbard Model

Ettore Vitali, Hao Shi, Adam Chiciak +1 more

Bulletin of the American Physical Society•Mar 5, 2018•0 citations

Ab initio extended Hubbard model of short polyenes for efficient quantum computing

Yuichiro Yoshida, Nayuta Takemori, Wataru Mizukami

We propose introducing an extended Hubbard Hamiltonian derived via the ab initio downfolding method, which was originally formulated for periodic materials, toward efficient quantum computing of molecular electronic structure calculations. By utilizing this method, the first-principles Hamiltonian of chemical systems can be coarse-grained by eliminating the electronic degrees of freedom in higher energy space and reducing the number of terms of electron repulsion integral from O(N4) to O(N2). Our approach is validated numerically on the vertical excitation energies and excitation characters of ethylene, butadiene, and hexatriene. The dynamical electron correlation is incorporated within the framework of the constrained random phase approximation in advance of quantum computations, and the constructed models capture the trend of experimental and high-level quantum chemical calculation results. As expected, the L1-norm of the fermion-to-qubit mapped model Hamiltonians is significantly lower than that of conventional ab initio Hamiltonians, suggesting improved scalability of quantum computing. Those numerical outcomes and the results of the simulation of excited-state sampling demonstrate that the ab initio extended Hubbard Hamiltonian may hold significant potential for quantum chemical calculations using quantum computers.

arXiv:2404.01623•The Journal of Chemical Physics•Aug 28, 2024•6 citations

Ground-state energy of the Hubbard model: Cluster-perturbative results

Maciej M. Maśka

When electron correlations are important it is often necessary to use numerical methods to solve the Hamiltonian for a finite system (cluster) ``exactly.'' Unfortunately, such methods are restricted to small systems. We propose to combine the ``exact'' numerical diagonalization for small clusters with the perturbative calculations to take into account the intracluster as well as intercluster interactions.

arXiv:cond-mat/9802171•Physical review. B, Condensed matter•Apr 15, 1998•7 citations
A new, simple and efficient method is presented for calculation of the ground and a few excited states of Hubbard chain nanostructures. By using this method, the photoemission spectral function for organic charge transfer salt TTF-TCNQ, is calculated. For a chain with maximum 70 sites the result is in good agreement with the previous works but there is a difference for further number of sites in the chain, which is discussed in the text with all the specifics. We also show that a source of errors in density matrix renormalization group method for a one dimensional chain is the deficiency of the matrix product scheme for generating the desired states of the linear chain.
We apply our new method of approach to electronic states in correlated systems [for a brief review, Part I, see: Acta Phys. Pol. B31, 2879 (2000)] to the analysis of the states and electron localization in nanoscopic chains containing up to N = 12 atoms. The Mott and the Hubbard criteria of localization are explicitly evaluated and the importance of the former is stressed. We also define the many-particle wave function and calculate it explicitly for the hydrogen molecule. Further applications of our method are listed at the end.
We propose introducing an extended Hubbard Hamiltonian derived via the ab initio downfolding method, which was originally formulated for periodic materials, toward efficient quantum computing of molecular electronic structure calculations. By utilizing this method, the first-principles Hamiltonian of chemical systems can be coarse-grained by eliminating the electronic degrees of freedom in higher energy space and reducing the number of terms of electron repulsion integral from O(N4) to O(N2). Our approach is validated numerically on the vertical excitation energies and excitation characters of ethylene, butadiene, and hexatriene. The dynamical electron correlation is incorporated within the framework of the constrained random phase approximation in advance of quantum computations, and the constructed models capture the trend of experimental and high-level quantum chemical calculation results. As expected, the L1-norm of the fermion-to-qubit mapped model Hamiltonians is significantly lower than that of conventional ab initio Hamiltonians, suggesting improved scalability of quantum computing. Those numerical outcomes and the results of the simulation of excited-state sampling demonstrate that the ab initio extended Hubbard Hamiltonian may hold significant potential for quantum chemical calculations using quantum computers.