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Related papers: Worm Improved Estimators in Continuous-time Quantu…

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We extend the continuous-time interaction-expansion quantum Monte Carlo method with respect to measuring observables for fermion-boson lattice models. Using generating functionals, we express expectation values involving boson operators,…

Strongly Correlated Electrons · Physics 2017-01-04 Manuel Weber , Fakher F. Assaad , Martin Hohenadler

We propose a generalization of the Quantum Monte Carlo loop algorithm to the t-J model by a mapping to three coupled six-vertex models. The autocorrelation times are reduced by orders of magnitude compared to the conventional local…

Strongly Correlated Electrons · Physics 2007-05-23 Beat Ammon , Hans Gerd Evertz , Naoki Kawashima , Matthias Troyer , Beat Frischmuth

A precise dynamical characterization of quantum impurity models with multiple interacting orbitals is challenging. In quantum Monte Carlo methods, this is embodied by sign problems. A dynamical sign problem makes it exponentially difficult…

Mesoscale and Nanoscale Physics · Physics 2024-07-02 Andre Erpenbeck , Thomas Blommel , Lei Zhang , Wei-Ting Lin , Guy Cohen , Emanuel Gull

We present the ground state extension of the efficient quantum Monte Carlo algorithm for lattice fermions of arXiv:1411.0683. Based on continuous-time expansion of imaginary-time projection operator, the algorithm is free of systematic…

Strongly Correlated Electrons · Physics 2015-07-02 Lei Wang , Mauro Iazzi , Philippe Corboz , Matthias Troyer

We present a numerically exact steady-state inchworm Monte Carlo method for nonequilibrium quantum impurity models. Rather than propagating an initial state to long times, the method is directly formulated in the steady-state. This…

Strongly Correlated Electrons · Physics 2023-05-17 André Erpenbeck , Emanuel Gull , Guy Cohen

We present a technique that enables the evaluation of perturbative expansions based on one-loop-renormalized vertices up to large expansion orders. Specifically, we show how to compute large-order corrections to the random phase…

Strongly Correlated Electrons · Physics 2020-11-19 Fedor Šimkovic , Riccardo Rossi , Michel Ferrero

World-line quantum Monte Carlo methods are reviewed with an emphasis on breakthroughs made in recent years. In particular, three algorithms -- the loop algorithm, the worm algorithm, and the directed-loop algorithm -- for updating…

Disordered Systems and Neural Networks · Physics 2009-11-10 Naoki Kawashima , Kenji Harada

We review the path-integral quantum Monte Carlo method and discuss its implementation by multiworm algorithms. We analyze in details the features of the algorithms, and focus our attention on the computation of the $N$-body density matrix…

Quantum Physics · Physics 2018-09-26 F. Lingua , B. Capogrosso-Sansone , A. Safavi-Naini , A. J. Jahangiri , V. Penna

We demonstrate that the ``worm'' algorithm allows very effective and precise quantum Monte Carlo (QMC) simulations of spin systems in a magnetic field, and its auto-correlation time is rather insensitive to the value of H at low…

Strongly Correlated Electrons · Physics 2007-05-23 V. A. Kashurnikov , N. V. Prokof'ev , B. V. Svistunov , M. Troyer

Compact and accurate wave functions can be constructed by quantum Monte Carlo methods. Typically, these wave functions consist of a sum of a small number of Slater determinants multiplied by a Jastrow factor. In this paper we study the…

Condensed Matter · Physics 2009-10-30 Chien-Jung Huang , C. J. Umrigar , M. P. Nightingale

This project investigates the applicability of quasi-Monte Carlo methods to Euclidean lattice systems in order to improve the asymptotic error scaling of observables for such theories. The error of an observable calculated by averaging over…

High Energy Physics - Lattice · Physics 2013-11-20 Andreas Ammon , Tobias Hartung , Karl Jansen , Hernan Leovey , Andreas Griewank , Micheal Müller-Preussker

We present results for lattice QCD in the limit of infinite gauge coupling on a discrete spatial but continuous Euclidean time lattice. A worm type Monte Carlo algorithm is applied in order to sample two-point functions which gives access…

High Energy Physics - Lattice · Physics 2018-11-06 Marc Klegrewe , Wolfgang Unger

The Variational Monte Carlo method has recently seen important advances through the use of neural network quantum states. While more and more sophisticated ans\"atze have been designed to tackle a wide variety of quantum many-body problems,…

Nuclear Theory · Physics 2025-07-09 M. Drissi , J. W. T. Keeble , J. Rozalén Sarmiento , A. Rios

Quantum impurity models describe an atom or molecule embedded in a host material with which it can exchange electrons. They are basic to nanoscience as representations of quantum dots and molecular conductors and play an increasingly…

Strongly Correlated Electrons · Physics 2011-05-09 Emanuel Gull , Andrew J. Millis , Alexander I. Lichtenstein , Alexey N. Rubtsov , Matthias Troyer , Philipp Werner

We describe a number of strategies for minimizing and calculating accurately the statistical uncertainty in quantum Monte Carlo calculations. We investigate the impact of the sampling algorithm on the efficiency of the variational Monte…

Computational Physics · Physics 2012-02-14 R. M. Lee , G. J. Conduit , N. Nemec , P. Lopez Rios , N. D. Drummond

We present a universal quantum Monte Carlo algorithm for simulating arbitrary high-spin (spin greater than 1/2) Hamiltonians, based on the recently developed permutation matrix representation (PMR) framework. Our approach extends a…

Computational Physics · Physics 2026-01-27 Arman Babakhani , Lev Barash , Itay Hen

We use a variational Monte Carlo algorithm to solve the electronic structure of two-dimensional semiconductor quantum dots in external magnetic field. We present accurate many-body wave functions for the system in various magnetic field…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Ari Harju

We develop a novel Monte Carlo algorithm for the vector consisting of the supremum, the time at which the supremum is attained and the position at a given (constant) time of an exponentially tempered L\'evy process. The algorithm, based on…

Mathematical Finance · Quantitative Finance 2023-11-20 Jorge Ignacio González Cázares , Aleksandar Mijatović

Two cluster algorithms, based on constructing and flipping loops, are presented for worldline quantum Monte Carlo simulations of fermions and are tested on the one-dimensional repulsive Hubbard model. We call these algorithms the loop-flip…

Condensed Matter · Physics 2007-05-23 N. Kawashima , J. E. Gubernatis , H. G. Evertz

We study the lattice O(2N) Gross-Neveu model with Wilson fermions in the fermion loop formulation. Employing a worm algorithm for an open fermionic string, we simulate fluctuating topological boundary conditions and use them to tune the…

High Energy Physics - Lattice · Physics 2015-03-19 Vidushi Maillart , Urs Wenger