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Related papers: Ab-initio path integral techniques for molecules

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We used methods of Bayesian statistical inference and the principle of maximum entropy to analytically continue imaginary-time Green's function generated in quantum Monte Carlo simulations to obtain the real-time Green's functions. For test…

Condensed Matter · Physics 2009-10-28 J. Bonca , J. E. Gubernatis

A novel scheme to solve the quantum eigenvalue problem through the imaginary-time Green function Monte Carlo method is presented. This method is applicable to the excited states as well as to the ground state of a generic system. We…

Nuclear Theory · Physics 2008-11-26 Taksu Cheon

A numerical algorithm based on the probabilistic path integral approach for solving Schroedinger equation has been devised to treat molecular systems without Born-Oppenheimer approximation in the non relativistic limit at zero temperature…

Quantum Physics · Physics 2023-02-28 Sumita Datta

Restricted path integral Monte Carlo simulations are used to calculate the equilibrium properties of hydrogen in the density and temperature range of $9.83 \times 10^{-4}\rm \leq \rho \leq 0.153 \rm gcm^{-3}$ and $5000 \leq T \leq 250 000…

Plasma Physics · Physics 2009-11-07 B. Militzer , D. M. Ceperley

The 'Neumann-Ulam' Monte-Carlo sampling is described for the calculation of a matrix inversion or a Green function in case of Hubbard-Stratonovich (HS-)transformed coherent state path integrals. We illustrate how to circumvent direct…

Statistical Mechanics · Physics 2012-05-23 Bernhard Mieck

A real-time path integral Monte Carlo approach is developed to study the dynamics in a many-body quantum system until reaching a nonequilibrium stationary state. The approach is based on augmenting an exact reduced equation for the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Lothar Mühlbacher , Eran Rabani

A quantum Monte Carlo method with non-local update scheme is presented. The method is based on a path-integral decomposition and a worm operator which is local in imaginary time. It generates states with a fixed number of particles and…

Statistical Mechanics · Physics 2009-11-11 Kris Van Houcke , Stefan Rombouts , Lode Pollet

The path-integral formulation of the statistical mechanics of quantum many-body systems is described, with the purpose of introducing practicaltechniques for the simulation of solids. Monte Carlo and molecular dynamics methods for…

Materials Science · Physics 2014-03-11 Carlos P. Herrero , Rafael Ramirez

An efficient Path Integral Monte Carlo procedure is proposed to simulate the behavior of quantum many-body dissipative systems described within the framework of the influence functional. Thermodynamic observables are obtained by Monte Carlo…

Statistical Mechanics · Physics 2009-11-07 Luca Capriotti , Alessandro Cuccoli , Andrea Fubini , Valerio Tognetti , Ruggero Vaia

The Markov chain Monte Carlo (MCMC) method is used to evaluate the imaginary-time path integral of a quantum oscillator with a potential that includes both a quadratic term and a quartic term whose coupling is varied by several orders of…

Computational Physics · Physics 2020-08-27 Shikhar Mittal , Marise J. E. Westbroek , Peter R. King , Dimitri D. Vvedensky

We investigate energy transport in several two-level atom or spin-1/2 models by a direct coupling to heat baths of different temperatures. The analysis is carried out on the basis of a recently derived quantum master equation which…

Quantum Physics · Physics 2009-11-13 Mathias Michel , Ortwin Hess , Hannu Wichterich , Jochen Gemmer

Thermodynamic properties of a strongly coupled quark-gluon plasma (QGP) of constituent quasiparticles are studied by a color path-integral Monte Carlo simulations (CPIMC). For our simulations we have presented QGP partition function in the…

High Energy Physics - Phenomenology · Physics 2012-03-13 V. S. Filinov , Yu. B. Ivanov , M. Bonitz , V. E. Fortov , P. R. Levashov

A newly developed method for systematically improving the convergence of path integrals for transition amplitudes, introduced in Phys. Rev. Lett. 94 (2005) 180403, Phys. Rev. B 72 (2005) 064302, Phys. Lett. A 344 (2005) 84, and expectation…

Statistical Mechanics · Physics 2011-08-08 Danica Stojiljkovic , Aleksandar Bogojevic , Antun Balaz

Variational Monte Carlo and Green's function Monte Carlo are powerful tools for calculations of properties of light nuclei using realistic two-nucleon and three-nucleon potentials. Recently the GFMC method has been extended to multiple…

Nuclear Theory · Physics 2009-11-10 Steven C. Pieper

We present results for many-body perturbation theory for the one-body Green's function at finite temperatures using the Matsubara formalism. Our method relies on the accurate representation of the single-particle states in standard Gaussian…

Strongly Correlated Electrons · Physics 2018-04-04 Michael Schüler , Yaroslav Pavlyukh

We present an \textit{ab initio} auxiliary field quantum Monte Carlo method for studying the electronic structure of molecules, solids, and model Hamiltonians at finite temperature. The algorithm marries the \textit{ab initio} phaseless…

Strongly Correlated Electrons · Physics 2018-11-13 Yuan Liu , Minsik Cho , Brenda Rubenstein

We introduce a Path Integral Monte Carlo (PIMC) approach that uses the angular momentum representation for the description of interacting rotor systems. Such a choice of representation allows the calculation of momentum properties without…

Chemical Physics · Physics 2025-10-22 Estêvão de Oliveira , Muhammad Shaeer Moeed , Pierre-Nicholas Roy

We introduce a quantum Monte Carlo technique to calculate exactly at finite temperatures the Green function of a fermionic quantum impurity coupled to a bosonic field. While the algorithm is general, we focus on the single impurity Anderson…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Liliana Arrachea , Marcelo J. Rozenberg

The discrete time path integral Monte Carlo (PIMC) with a one-particle density matrix approximation is applied to study the quantum phase transition in the coupled double-well chain. To improve the convergence properties, the exact action…

Statistical Mechanics · Physics 2015-06-25 Dong-Hee Kim , Yu-Cheng Lin , Heiko Rieger

We propose a bilinear sampling algorithm in Green's function Monte Carlo for expectation values of operators that do not commute with the Hamiltonian and for differences between eigenvalues of different Hamiltonians. The integral…

Condensed Matter · Physics 2010-01-12 Shiwei Zhang , M. H. Kalos