An Improvement on the Negative Sign Problem in Numerical Calculations of a Quantum Spin System

TL;DR

This paper introduces a novel numerical approach for quantum spin systems that significantly mitigates the negative sign problem by utilizing any complete set of states in path integral calculations.

Contribution

The authors propose a new method leveraging complete state sets for path integrals, improving the negative sign problem in quantum spin system simulations.

Findings

Significant reduction in negative sign problem.

Effective for one-dimensional quantum spin systems with next-to-nearest neighbor interactions.

Potential for broader application in quantum Monte Carlo methods.

Abstract

We propose new approach to numerical study of quantum spin systems. Our method is based on a fact that one can use any set of states for the path integral as long as it is complete. We apply our method to one-dimensional quantum spin system with next-to-nearest neighbor interactions. We found remarkable improvement in negative sign problem.