Particle-wave dichotomy in quantum Monte Carlo: unlocking the quantum correlations

TL;DR

This paper introduces a quantum Monte Carlo method employing a particle-wave dichotomy with stochastic ensembles to accurately simulate electron dynamics and decoherence in quantum systems, bypassing the need for full many-body states.

Contribution

It presents a novel stochastic sampling approach combining particle and wave aspects to efficiently predict quantum electron behavior in complex systems.

Findings

Successfully predicts ground state and real-time electron evolution

Accurately models decoherence due to Coulomb interactions

Avoids referencing full many-body quantum states

Abstract

Here, a dichotomy of particles and waves is employed in a quantum Monte Carlo calculation of interacting electrons. Through the creation and propagation of concurrent stochastic ensembles of walkers in physical space and in Hilbert space one can correctly predict the ground state and the real-time evolution of a single electron interacting with larger quantum system. It is shown that such walker ensembles can be constructed straightforwardly through a stochastic sampling (windowing) applied to the mean-field approximation. Our calculations reveal that the ground state and the real-time evolution of the probability distributions and the decoherence due to the Coulomb interaction in presence of strong ultrashort laser pulse can be accounted for correctly by calculating the density matrix of the electron, without referencing to the quantum many-body state of the whole system.