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Related papers: On the evaluation of matrix elements in partially …

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We analyze within a semiclassical approximation the form factor for the fluctuations of quantum matrix elements around their classical average. We find two contributions: one is proportional to the form factor for the density of states,…

chao-dyn · Physics 2009-10-28 Bruno Eckhardt , Joerg Main

We investigate spin and orbital states of the two-orbital Hubbard model on a square lattice by using a variational Monte Carlo method at quarter-filling, i.e., the electron number per site is one. As a variational wave function, we consider…

Strongly Correlated Electrons · Physics 2009-08-07 Katsunori Kubo

This paper is devoted to parameter estimation for partially observed polynomial state space models. This class includes discretely observed affine or more generally polynomial Markov processes. The polynomial structure allows for the…

Statistics Theory · Mathematics 2025-07-11 Jan Kallsen , Ivo Richert

We propose an efficient numerical method, which combines the advantages of recently developed tensor-network based methods and standard trial wave functions, to study the ground state properties of quantum many-body systems. In this…

Strongly Correlated Electrons · Physics 2015-05-22 Olga Sikora , Hsueh-Wen Chang , Chung-Pin Chou , Frank Pollmann , Ying-Jer Kao

We discuss the Hubbard model in an applied magnetic field and analyze the properties of neutral spin-1/2 fermions within the so-called statistically consistent Gutzwiller approximation (SGA). The magnetization curve reproduces in a…

Strongly Correlated Electrons · Physics 2014-07-28 Marcin M. Wysokinski , Jozef Spalek

Thomas-Fermi theory is developed to evaluate nuclear matrix elements averaged on the energy shell, on the basis of independent particle Hamiltonians. One- and two-body matrix elements are compared with the quantal results and it is…

Nuclear Theory · Physics 2010-12-23 X. Vinas , P. Schuck , M. Farine , M. Centelles

We study in this paper a series of Gutzwiller Projected wavefunctions for S=1 spin chains obtained from a fermionic mean-field theory for general S>1/2 spin systems [Phys. Rev. B 81, 224417] applied to the bilinear-biquadratic (J-K) model.…

Strongly Correlated Electrons · Physics 2012-05-30 Zheng-Xin Liu , Yi Zhou , Hong-Hao Tu , Xiao-Gang Wen , Tai-Kai Ng

We analyze the electronic Green's functions in the superconducting ground state of the t-J model using Gutzwiller-projected wave functions, and compare them to the conventional BCS form. Some of the properties of the BCS state are preserved…

Strongly Correlated Electrons · Physics 2011-11-09 Samuel Bieri , Dmitri Ivanov

The effective Hamiltonian of strongly correlated electrons on a square lattice is replaced by a renormalised Hamiltonian and the factors that renormalise the kinetic energy of holes and the Heisenberg spin-spin coupling are calculated using…

Strongly Correlated Electrons · Physics 2007-05-23 F. C. Zhang , C. Gros , T. M. Rice , H. Shiba

We present a numerically efficient method for the characterisation of a quantum process subject to dissipation and noise. The master equation evolution of a maximally entangled state of the quantum system and a non-evolving ancilla system…

Quantum Physics · Physics 2013-12-04 Jake Gulliksen , D. D. Bhaktavatsala Rao , Klaus Mølmer

The Fisher matrix (FM) has been generally used to predict the accuracy of the gravitational wave parameter estimation. Although a limitation of the FM has been well known, it is still mainly used due to its very low computational cost…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Hee-Suk Cho , Chang-Hwan Lee

The Mott transition is usually considered as resulting from the divergence of the effective mass of the quasiparticle in the Fermi-liquid theory; the dispersion relation around the Fermi level is considered to become flat towards the Mott…

Strongly Correlated Electrons · Physics 2020-10-26 Masanori Kohno

Parametric regularity of discretizations of flux vector fields satisfying a balance law is studied under some assumptions on a random parameter that links the flux with an unknown primal variable (often through a constitutive law). In the…

Numerical Analysis · Mathematics 2026-04-07 Vesa Kaarnioja , Andreas Rupp , Jay Gopalakrishnan

Two-dimensional t-J model is studied by a variational Monte Carlo method, using Gutzwiller-Jastrow-type wave functions. Various kinds of superconducting pairing symmetries are compared in order to determine the phase diagram of the ground…

Condensed Matter · Physics 2009-10-28 Hisatoshi Yokoyama , Masao Ogata

Through Variational Monte Carlo simulation we show the d-wave RVB pairing in the Heisenberg model on triangular lattice can be better described in terms of a two component order parameter. The fully gapped chiral d-wave RVB state, which is…

Strongly Correlated Electrons · Physics 2010-05-18 Tao Li

The Gutzwiller approximate solution to the Gutzwiller wavefunction yields exact results for the Gutzwiller wavefunction in the infinite dimensional limit. Implicit in the Gutzwiller approximation is an approximate local form of the fermion…

Strongly Correlated Electrons · Physics 2009-07-27 Balazs Hetenyi , Hans Gerd Evertz , Wolfgang von der Linden

We provide a pedagogical introduction to the two main variants of real-space quantum Monte Carlo methods for electronic-structure calculations: variational Monte Carlo (VMC) and diffusion Monte Carlo (DMC). Assuming no prior knowledge on…

Chemical Physics · Physics 2015-08-13 Julien Toulouse , Roland Assaraf , C. J. Umrigar

Implicit particle filtering is a sequential Monte Carlo method for data assim- ilation, designed to keep the number of particles manageable by focussing attention on regions of large probability. These regions are found by min- imizing, for…

Numerical Analysis · Mathematics 2015-05-30 Matthias Morzfeld , Alexandre J. Chorin

The two-dimensional Hubbard model is studied using the variational quantum Monte Carlo technique with Gutzwiller-type variational wave functions. In addition to the simple one-site correlated Gutzwiller wave function, we use a form with…

Strongly Correlated Electrons · Physics 2007-05-23 A. Harju

Magnetization process of the Gutzwiller wave function is studied accurately by a variational Monte Carlo method. We apply it to the one-dimensional (1D) and 2D Hubbard models (HM), and to the 1D periodic Anderson model (PAM) without orbital…

Condensed Matter · Physics 2007-05-23 Hisatoshi Yokoyma , Shinya Tokizaki