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Related papers: Excited states in variational Monte Carlo using a …

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We present a Monte Carlo model for degradation of 1-10,000 eV electrons in an atmosphere of methane. The electron impact cross sections for CH4 are compiled and analytical representations of these cross sections are used as input to the…

Space Physics · Physics 2015-05-27 Anil Bhardwaj , Vrinda Mukundan

We introduce a general Monte Carlo scheme for achieving atomistic simulations with monoelectronic Hamiltonians including the thermalization of both nuclear and electronic degrees of freedom. The kinetic Monte Carlo algorithm is used to…

Materials Science · Physics 2009-11-07 F. Calvo , F. Spiegelman

We present a method to model the interaction and the dynamics of atoms excited to Rydberg states. We show a way to solve the optical Bloch equations for laser excitation of the frozen gas in good agreement with the experiment. A second…

Atomic Physics · Physics 2009-11-13 Amodsen Chotia , Matthieu Viteau , Thibault Vogt , Daniel Comparat , Pierre Pillet

We give a prescription for finding optimized correlation functions for the extraction of the gap to the first excited state within quantum Monte Carlo simulations. We demonstrate that optimized correlation functions provide a more accurate…

Statistical Mechanics · Physics 2012-03-20 Itay Hen

We introduce state-averaging into the method of Monte Carlo configuration interaction (SA-MCCI) to allow the stable and efficient calculation of excited states. We show that excited potential curves for H$_{3}$, including a crossing with…

Chemical Physics · Physics 2014-03-03 J. P. Coe , M. J. Paterson

Excited states of spin-chains play an important role in condensed matter physics. We present a method of calculating the single magnon excited states of the Heisenberg spin-chain that can be efficiently implemented on a quantum processor…

Strongly Correlated Electrons · Physics 2022-11-23 Shashank Kumar Ranu , Daniel D. Stancil

An appropriate iterative scheme for the minimization of the energy, based on the variational Monte Carlo (VMC) technique, is introduced and compared with existing stochastic schemes. We test the various methods for the 1D Heisenberg ring…

Strongly Correlated Electrons · Physics 2009-11-11 Sandro Sorella

We report quantum Monte Carlo calculations of ground and low-lying excited states for nuclei with A \leq 7 using a realistic Hamiltonian containing the Argonne v18 two-nucleon and Urbana IX three-nucleon potentials. A detailed description…

Nuclear Theory · Physics 2008-11-26 B. S. Pudliner , V. R. Pandharipande , J. Carlson , Steven C. Pieper , R. B. Wiringa

Multi-dimensional density of states provides a useful description of complex frustrated systems. Recent advances in Monte Carlo methods enable efficient calculation of the density of states and related quantities, which renew the interest…

Disordered Systems and Neural Networks · Physics 2009-11-10 Yukito Iba , Hisanao Takahashi

Monte Carlo methods are widely used importance sampling techniques for studying complex physical systems. Integrating these methods with deep learning has significantly improved efficiency and accuracy in high-dimensional problems and…

Disordered Systems and Neural Networks · Physics 2024-12-24 Yixiong Ren , Jianhui Zhou

Calculating the energy spectrum of a quantum system is an important task, for example to analyse reaction rates in drug discovery and catalysis. There has been significant progress in developing algorithms to calculate the ground state…

Quantum Physics · Physics 2019-06-12 Suguru Endo , Tyson Jones , Sam McArdle , Xiao Yuan , Simon Benjamin

In this paper we present a model for the electronic excited states of $\pi$ conjugated -acene molecules such as tetracene, pentacene, and hexacene. We use a simple Hubbard model with a limited basis to describe the low lying excitations…

Chemical Physics · Physics 2016-11-07 Z. S. Sadeq , J. E. Sipe

Monte Carlo techniques with importance sampling have been extensively applied to lattice gauge theory in the Lagrangian formulation. Unfortunately, it is extremely difficult to compute the excited states using the conventional Monte Carlo…

High Energy Physics - Lattice · Physics 2017-08-23 Xiang-Qian Luo , H. Jirari , H. Kroger , K. Moriarty

The diffusion Monte Carlo method with symmetry-based state selection is used to calculate the quantum energy states of H$_2^+$ confined into potential barriers of atomic dimensions (a model for these ions in solids). Special solutions are…

Chemical Physics · Physics 2019-04-03 Gaia Micca Longo , Savino Longo , Domenico Giordano

While recent work towards the development of tight-binding and ab-initio algorithms has focused on molecular dynamics, Monte Carlo methods can often lead to better results with relatively little effort. We present here a multi-step Monte…

Statistical Mechanics · Physics 2009-10-31 Parthapratim Biswas , G. T. Barkema , Normand Mousseau , W. F. van der Weg

We discuss a projector Monte Carlo method for quantum spin models formulated in the valence bond basis, using the S=1/2 Heisenberg antiferromagnet as an example. Its singlet ground state can be projected out of an arbitrary basis state as…

Strongly Correlated Electrons · Physics 2007-05-23 A. W. Sandvik , K. S. D. Beach

This article addresses online variational estimation in parametric state-space models. We propose a new procedure for efficiently computing the evidence lower bound and its gradient in a streaming-data setting, where observations arrive…

Methodology · Statistics 2026-02-09 Mathis Chagneux , Mathias Müller , Pierre Gloaguen , Sylvain Le Corff , Jimmy Olsson

In this paper we present a new approach to control variates for improving computational efficiency of Ensemble Monte Carlo. We present the approach using simulation of paths of a time-dependent nonlinear stochastic equation. The core idea…

Computational Engineering, Finance, and Science · Computer Science 2008-09-25 T. Borogovac , F. J. Alexander , P. Vakili

We develop a novel multi-configurational Symmetrized Projector Quantum Monte Carlo (MSPQMC) method to calculate excited state properties of Hubbard models. We compare the MSPQMC results for finite Hubbard chains with exact results (where…

Condensed Matter · Physics 2009-10-28 Bhargavi Srinivasan , S. Ramasesha , H. R. Krishnamurthy

We present a stable and systematically improvable quantum Monte Carlo (QMC) approach to calculating excited-state energies, which we implement using our fast randomized iteration method for the full configuration interaction problem…

Computational Physics · Physics 2023-10-03 Samuel M. Greene , Robert J. Webber , James E. T. Smith , Jonathan Weare , Timothy C. Berkelbach