Wavefunction correction scheme for non fixed-node diffusion Monte Carlo

TL;DR

This paper applies a wavefunction correction scheme to non fixed-node diffusion Monte Carlo, significantly reducing computation times for fermionic systems without relying on the fixed-node approximation.

Contribution

It demonstrates the effectiveness of wavefunction correction in non fixed-node DMC, enabling more efficient fermionic calculations without fixed-node constraints.

Findings

Reduced computation times in benchmark tests

Effective variance reduction in non fixed-node DMC

Applicable to fermionic systems without fixed-node approximation

Abstract

Wavefunction correction scheme, which was developed as a variance reduction tool for the pure and fixed-node diffusion Monte Carlo (DMC) computations by Anderson and Freihaut, is applied to the DMC computations of fermions without using the fixed-node constraint. This technique is found to be suitable for the non fixed-node calculations because of the significant decreases observed in the computation times for calculating results with certain statistical error values in the benchmark computations.