English

Path integral Monte Carlo in a discrete variable representation with Gibbs sampling: dipolar planar rotor chain

Chemical Physics 2026-01-23 v1 Mesoscale and Nanoscale Physics Statistical Mechanics Atomic and Molecular Clusters Quantum Physics

Abstract

In this work, we propose a Path Integral Monte Carlo (PIMC) approach based on discretized continuous degrees of freedom and rejection-free Gibbs sampling. The ground state properties of a chain of planar rotors with dipole-dipole interactions are used to illustrate the approach. Energetic and structural properties are computed and compared to exact diagonalization and Numerical Matrix Multiplication for N3N \leq 3 to assess the systematic Trotter factorization error convergence. For larger chains with up to N = 100 rotors, Density Matrix Renormalization Group (DMRG) calculations are used as a benchmark. We show that using Gibbs sampling is advantageous compared to traditional Metroplolis-Hastings rejection importance sampling. Indeed, Gibbs sampling leads to lower variance and correlation in the computed observables.

Keywords

Cite

@article{arxiv.2410.13633,
  title  = {Path integral Monte Carlo in a discrete variable representation with Gibbs sampling: dipolar planar rotor chain},
  author = {Wenxue Zhang and Muhammad Shaeer Moeed and Andrew Bright and Tobias Serwatka and Estevao De Oliveira and Pierre-Nicholas Roy},
  journal= {arXiv preprint arXiv:2410.13633},
  year   = {2026}
}
R2 v1 2026-06-28T19:25:59.608Z