English
Related papers

Related papers: Accelerated nuclear quantum effects sampling with …

200 papers

We apply the Generalised Thimble approach to the computation of exact path integrals and correlators in real-time quantum field theory. We first investigate the details of the numerical implementation and ways of optimizing the algorithm.…

High Energy Physics - Theory · Physics 2022-04-22 Simon Woodward , Paul M. Saffin , Zong-Gang Mou , Anders Tranberg

We theoretically analyze the dynamics of an atomic double-well system with a single ion trapped in its center. We find that the atomic tunnelling rate between the wells depends both on the spin of the ion via the short-range spin-dependent…

Quantum Physics · Physics 2015-06-19 Jannis Joger , Antonio Negretti , Rene Gerritsma

An improved real-time quantum Monte Carlo procedure is presented and applied to describe the electronic transfer dynamics along molecular chains. The model consists of discrete electronic sites coupled to a thermal environment which is…

Chemical Physics · Physics 2009-11-10 L. Muehlbacher , J. Ankerhold , C. Escher

Quantum simulation - the use of one quantum system to simulate a less controllable one - may provide an understanding of the many quantum systems which cannot be modeled using classical computers. Impressive progress on control and…

When tunneling occurs out of generic initial states, a significant fraction of probability is lost at early times during which the dynamics is governed by excited resonance states. However, first-principles analyses based on path integrals…

High Energy Physics - Theory · Physics 2025-11-13 Joshua Lin , Bruno Scheihing-Hitschfeld , Thomas Steingasser

Quantum Monte Carlo methods find fruitful application in large shell model problems. These methods reduce the imaginary-time many-body evolution operator to a coherent superposition of one-body evolutions in a fluctuating one-body field;…

Nuclear Theory · Physics 2008-02-03 S. E. Koonin

We propose a new Monte Carlo method for efficiently sampling trajectories with fixed initial and final conditions in a system with discrete degrees of freedom. The method can be applied to any stochastic process with local interactions,…

Statistical Mechanics · Physics 2012-03-30 Thierry Mora , Aleksandra M. Walczak , Francesco Zamponi

In current studies of mean-field quantum spin systems, much attention is placed on the calculation of the ground-state energy and the excitation gap, especially the latter which plays an important role in quantum annealing. In pure systems,…

Disordered Systems and Neural Networks · Physics 2018-03-26 Yang Wei Koh

We generalize a recently developed method for accelerated Monte Carlo calculation of path integrals to the physically relevant case of generic many-body systems. This is done by developing an analytic procedure for constructing a hierarchy…

Statistical Mechanics · Physics 2011-08-08 Aleksandar Bogojevic , Ivana Vidanovic , Antun Balaz , Aleksandar Belic

We consider tunneling processes in QFT induced by collisions of elementary particles. We propose a semiclassical method for estimating the probability of these processes in the limit of very high collision energy. As an illustration, we…

High Energy Physics - Theory · Physics 2009-11-10 D. Levkov , S. Sibiryakov

We present a new class of high-order imaginary time propagators for path-integral Monte Carlo simulations by subtracting lower order propagators. By requiring all terms of the extrapolated propagator be sampled uniformly, the subtraction…

Computational Physics · Physics 2015-05-13 Robert E. Zillich , Johannes M. Mayrhofer , Siu A. Chin

Monte Carlo simulations, in which the Schrodinger equation is solved at each Monte Carlo sweep, are employed to assess the influence of magnetization fluctuations,short-range antiferromagnetic interactions, disorder, magnetic polaron…

Materials Science · Physics 2007-05-23 D. Kechrakos , N. Papanikolaou , K. N. Trohidou , T. Dietl

In the absence of impurities and boundary effects, first order phase transitions are initiated by the nucleation of critical bubbles. In thermally driven transitions many systems can remain metastable for an extended time, possibly tens of…

High Energy Physics - Lattice · Physics 2025-02-21 Jaakko Hällfors , Kari Rummukainen

We develop a new simulation technique based on path-integral molecular dynamics for calculating ground-state tunneling splitting patterns from ratios of symmetrized partition functions. In particular, molecular systems are rigorously…

In this work, a path integral Car-Parrinello molecular dynamics simulation of liquid water is performed. It is found that the inclusion of nuclear quantum effects systematically improves the agreement of first principles simulations of…

Soft Condensed Matter · Physics 2009-11-13 Joseph A. Morrone , Roberto Car

Unbiased stochastic sampling of the one- and two-body reduced density matrices is achieved in full configuration interaction quantum Monte Carlo with the introduction of a second, "replica" ensemble of walkers, whose population evolves in…

Computational Physics · Physics 2015-09-02 Robert E. Thomas , Daniel Opalka , Catherine Overy , Peter J. Knowles , Ali Alavi , George H. Booth

Artificial Neural Networks were recently shown to be an efficient representation of highly-entangled many-body quantum states. In practical applications, neural-network states inherit numerical schemes used in Variational Monte Carlo, most…

Disordered Systems and Neural Networks · Physics 2020-01-22 Or Sharir , Yoav Levine , Noam Wies , Giuseppe Carleo , Amnon Shashua

An effective simulation of quantum entanglement is presented using classical fields modulated with n pseudorandom phase sequences (PPSs) that constitute a n2^n-dimensional Hilbert space with a tensor product structure. Applications to…

Quantum Physics · Physics 2015-03-17 Jian Fu , Xingkun Wu

Recent experiments have confirmed the importance of nuclear quantum effects even in large biomolecules at physiological temperature. Here we describe how the path integral formalism can be used to describe rigorously the nuclear quantum…

Chemical Physics · Physics 2012-07-03 Tomas Zimmermann , Jiri Vanicek