English
Related papers

Related papers: Ab initio path integral Monte Carlo simulations of…

200 papers

Quantum Monte-Carlo (QMC) simulations involving fermions have the notorious sign problem. Some well-known exceptions of the auxiliary field QMC algorithm rely on the factorizibility of the fermion determinant. Recently, a fermionic QMC…

Strongly Correlated Electrons · Physics 2009-02-06 Congjun Wu , Shou-Cheng Zhang

The auxiliary-field quantum Monte Carlo (AFMC) method is a powerful and widely used technique for ground-state and finite-temperature simulations of quantum many-body systems. We introduce several algorithmic improvements for…

Computational Physics · Physics 2021-03-18 C. N. Gilbreth , S. Jensen , Y. Alhassid

The path integral formulation of quantum mechanical problems including fermions is often affected by a severe numerical sign problem. We show how such a sign problem can be alleviated by a judiciously chosen constant imaginary offset to the…

Strongly Correlated Electrons · Physics 2024-10-23 Christoph Gäntgen , Evan Berkowitz , Thomas Luu , Johann Ostmeyer , Marcel Rodekamp

We present Monte Carlo calculations of the thermodynamics of the (2+1) dimensional Thirring model at finite density. We bypass the sign problem by deforming the domain of integration of the path integral into complex space in such a way as…

High Energy Physics - Lattice · Physics 2018-11-14 Andrei Alexandru , Paulo F. Bedaque , Henry Lamm , Scott Lawrence , Neill C. Warrington

In this paper, we discover a new quantum Monte Carlo (QMC) method to solve the fermion sign problem in interacting fermion models by employing Majorana representation of complex fermions. We call it "Majorana QMC" (MQMC). Especially, MQMC…

Strongly Correlated Electrons · Physics 2015-07-22 Zi-Xiang Li , Yi-Fan Jiang , Hong Yao

A path-integral hybrid Monte Carlo approach with enveloping bridging potentials (PIHMC-EBP) is proposed for calculating numerically exact tunneling splittings in molecular systems. The central idea is to construct an approximately…

Chemical Physics · Physics 2026-04-15 Yu-Chen Wang , Jeremy O. Richardson

Thermodynamics of dissipative quantum systems with double-well potentials is studied by the path-integral Monte Carlo (PIMC) method without truncation to the two-state model. For efficient simulation at low temperatures, we develop a new…

Statistical Mechanics · Physics 2007-05-23 Takeshi Matsuo , Yuhei Natsume , Takeo Kato

The Wigner formulation of quantum mechanics is used to derive a new path integral representation of quantum density of states. A path integral Monte Carlo approach is developed for the numerical investigation of density of states, internal…

Computational Physics · Physics 2023-09-12 V. Filinov , P. Levashov , A. Larkin

For important classes of many-fermion problems, quantum Monte Carlo (QMC) methods allow exact calculations of ground-state and finite-temperature properties, without the sign problem. The list spans condensed matter, nuclear physics, and…

Computational Physics · Physics 2016-03-23 Hao Shi , Shiwei Zhang

We have systematically studied the thermodynamic properties of a two-dimensional half-filled SU(2N) Hubbard model on a square lattice by using the determinant quantum Monte Carlo method. The entropy-temperature relation, the isoentropy…

Quantum Gases · Physics 2015-02-02 Zhichao Zhou , Zi Cai , Congjun Wu , Yu Wang

Monte Carlo simulations are a powerful tool for elucidating the properties of complex systems across many disciplines. Not requiring any a priori knowledge, they are particularly well suited for exploring new phenomena. However, when…

Strongly Correlated Electrons · Physics 2016-03-02 Mauro Iazzi , Alexey A. Soluyanov , Matthias Troyer

The quantum theory of the Friedmann cosmological model with dust and cosmological constant ($\Lambda$) is not exactly solvable analytically. We apply Path Integral Monte Carlo (PIMC) techniques to study its quantum dynamics using the…

General Relativity and Quantum Cosmology · Physics 2020-09-10 Masooma Ali , Syed Moeez Hassan , Viqar Husain

The Quantum Monte Carlo method for spin 1/2 fermions at finite temperature is formulated for dilute systems with an s-wave interaction. The motivation and the formalism are discussed along with descriptions of the algorithm and various…

Statistical Mechanics · Physics 2009-02-05 Aurel Bulgac , Joaquin E. Drut , Piotr Magierski

We show that Monte Carlo sampling of the Feynman diagrammatic series (DiagMC) can be used for tackling hard fermionic quantum many-body problems in the thermodynamic limit by presenting accurate results for the repulsive Hubbard model in…

Strongly Correlated Electrons · Physics 2015-05-13 E. Kozik , K. Van Houcke , E. Gull , L. Pollet , N. Prokof'ev , B. Svistunov , M. Troyer

We study spin-dipole oscillations of a binary fermionic mixture at nonzero temperatures. We apply the atomic-orbital method combined with the Monte Carlo technique based sampling to probe finite temperatures. Our results agree…

Quantum Gases · Physics 2020-01-22 Jarosław Ryszkiewicz , Mirosław Brewczyk , Tomasz Karpiuk

At low temperatures $T$ where $1/T=\beta\gg1$ the na\"ive implementation of determinant quantum Monte Carlo (DQMC) methods suffers from loss of precision and numerical instabilities when evaluating the fermion determinant. This instability…

Computational Physics · Physics 2026-04-02 Thomas Luu , Johann Ostmeyer , Petar Sinilkov , Finn L. Temmen

The accurate description of electrons at extreme density and temperature is of paramount importance for, e.g., the understanding of astrophysical objects and inertial confinement fusion. In this context, the dynamic structure factor…

Plasma Physics · Physics 2018-12-26 T. Dornheim , S. Groth , J. Vorberger , M. Bonitz

Quantum Monte Carlo (QMC) methods are one of the most important tools for studying interacting quantum many-body systems. The vast majority of QMC calculations in interacting fermion systems require a constraint to control the sign problem.…

Strongly Correlated Electrons · Physics 2016-12-08 Mingpu Qin , Hao Shi , Shiwei Zhang

Strongly-coupled fermionic systems can support a variety of low-energy phenomena, giving rise to collective condensation, symmetry breaking and a rich phase structure. We explore the potential of worldline Monte Carlo methods for analyzing…

High Energy Physics - Theory · Physics 2010-11-11 Gerald Dunne , Holger Gies , Klaus Klingmuller , Kurt Langfeld

We formulate a path-integral Monte Carlo algorithm for simulating lattice systems consisting of fictitious particles governed by a generalized exchange statistics. This method, initially proposed for continuum systems, introduces a…

Strongly Correlated Electrons · Physics 2025-08-19 Zhijie Fan , Tianning Xiao , Youjin Deng