English
Related papers

Related papers: Efficient algorithm based on Liechtenstein method …

200 papers

We present an optimised multipole algorithm for computing the three-point correlation function (3PCF), tailored for application to large-scale cosmological datasets. The algorithm builds on a $in\, situ$ interpretation of correlation…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 Wenjie Ju , Longlong Feng , Zhiqi Huang , Xin Sun , Weishan Zhu

In this paper the efficient space virtualisation for Hoshen--Kopelman algorithm is presented. We observe minimal parallel overhead during computations, due to negligible communication costs. The proposed algorithm is applied for computation…

Computational Physics · Physics 2019-08-21 M. Kotwica , P. Gronek , K. Malarz

IFOSMONDI iterative algorithm for implicit co-simulation of coupled physical systems (introduced by the authors in july 2019 during the Simultech conference, p.176-186) enables us to solve the nonlinear coupling function while keeping the…

Numerical Analysis · Mathematics 2021-01-13 Yohan Eguillon , Bruno Lacabanne , Damien Tromeur-Dervout

Exchange couplings are calculated for Li2VOSiO4 using LDA. While the sum of in-plane couplings J_1 + J_2 = 9.5 \pm 1.5 K and the inter-plane coupling J_{perp} \sim 0.2 - 0.3 K agree with recent experimental data, the ratio J_2/J_1 \sim 12…

Strongly Correlated Electrons · Physics 2009-11-07 H. Rosner , R. R. P. Singh , W. H. Zheng , J. Oitmaa , S. L. Drechsler , W. E. Pickett

We present an accelerated algorithm for the solution of static Hamilton-Jacobi-Bellman equations related to optimal control problems. Our scheme is based on a classic policy iteration procedure, which is known to have superlinear…

Optimization and Control · Mathematics 2016-02-22 Alessandro Alla , Maurizio Falcone , Dante Kalise

We present a fast and exact method for computing CMB mode-coupling matrices based on an optimised evaluation of Wigner-3j symbols. The method exploits analytic structure in the relevant Wigner-3j symbol configurations appearing in…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-18 Georgia Kiddier , Steven Gratton

We present enhancements to the computational efficiency of exact exchange calculations using the density matrix and local support functions. We introduce a numerical method which avoids the explicit calculation the four-center two-electron…

Chemical Physics · Physics 2016-11-25 Lionel A. Truflandier , Tsuyoshi Miyazaki , David R. Bowler

Exchange coupling parameters $J_{ij}$ in the Heisenberg model are crucial for describing magnetic behavior at the atomic level. In magnetic materials, spin fluctuations can be accompanied by a self-consistent electronic response --…

Materials Science · Physics 2026-03-05 Tomonori Tanaka , Yoshihiro Gohda

We present a detailed analysis of the spin models with near-neighbors interactions constructed in our previous paper [Phys. Lett. B 605 (2005) 214] by a suitable generalization of the exchange operator formalism. We provide a complete…

Exactly Solvable and Integrable Systems · Physics 2008-11-26 A. Enciso , F. Finkel , A. Gonzalez-Lopez , M. A. Rodriguez

Multisite local orbitals, which are formed from linear combinations of pseudo-atomic orbitals from a target atom and its neighbor atoms, have been introduced in the large-scale density functional theory calculation code CONQUEST. Multisite…

Materials Science · Physics 2014-11-11 Ayako Nataka , David R. Bowler , Tsuyoshi Miyazaki

We present a nonequilibrium strong-coupling approach to inhomogeneous systems of ultracold atoms in optical lattices. We demonstrate its application to the Mott-insulating phase of a two-dimensional Fermi-Hubbard model in the presence of a…

Strongly Correlated Electrons · Physics 2014-02-25 A. Dirks , K. Mikelsons , H. R. Krishnamurthy , J. K. Freericks

We consider a new quantum gate mechanism based on electron spins in coupled semiconductor quantum dots. Such gates provide a general source of spin entanglement and can be used for quantum computers. We determine the exchange coupling J in…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Guido Burkard , Daniel Loss , David P. DiVincenzo

In computational molecular science, calculation of electrostatic interactions involving charged atoms - the strongest interactions in condensed phases, is a major bottleneck. We propose a quantum-classical algorithm for fast, yet, accurate…

Quantum Physics · Physics 2026-02-18 Mansur Ziiatdinov , Igor Novikov , Farid Ablayev , Valeri Barsegov

The exchange interaction is a foundational building block for the operation of spin-based quantum processors. Extracting the exchange interaction coefficient $J(\mathbf{V})$, as a function of gate electrode voltages, is important for…

Mesoscale and Nanoscale Physics · Physics 2026-05-11 Dylan Albrecht , Sarah Thompson , N. Tobias Jacobson , Ryan Jock

We have used exact numerical diagonalization to study the excitation spectrum and the dynamic spin correlations in the $s=1/2$ next-next-nearest neighbor Heisenberg antiferromagnet on the square lattice, with additional 4-spin ring exchange…

Strongly Correlated Electrons · Physics 2019-03-06 C. B. Larsen , A. T. Rømer , S. Janas , F. Treue , B. Mønsted , N. E. Shaik , H. M. Rønnow , K. Lefmann

Many physical systems can be adequately modelled using a second order approximation. The problem of plant identification reduces to the problem of estimating the position of a single pair of complex conjugate poles. One approach to the…

Data Analysis, Statistics and Probability · Physics 2012-11-19 Andrew Allison , Derek Abbott

The evaluation of exact (Hartree--Fock, HF) exchange operator is a crucial ingredient for the accurate description of electronic structure in periodic systems through ab initio and hybrid density functional approaches. An efficient…

Chemical Physics · Physics 2020-10-28 Xiao Wang , Cannada A. Lewis , Edward F. Valeev

We study the accuracy of analytical wave function based many-body methods derived by energy minimization of a Jastrow-Feenberg ansatz for electrons (`Fermi hypernetted chain / Euler Lagrange' approach). Approximations to avoid the…

Other Condensed Matter · Physics 2019-06-05 Martin Panholzer , Raphael Hobbiger , Helga Böhm

Local electronic-structure methods in quantum chemistry operate on the ability to compress electron correlations more efficiently in a basis of spatially localized molecular orbitals than in a parent set of canonical orbitals. However, many…

Chemical Physics · Physics 2024-08-01 Jonas Greiner , Jürgen Gauss , Janus J. Eriksen

We present a novel approach to calculate the effective exchange interaction parameters based on the realistic electronic structure of correlated magnetic crystals in local approach with the frequency dependent self energy. The analog of…

Strongly Correlated Electrons · Physics 2009-10-31 M. I. Katsnelson , A. I. Lichtenstein