Abstract

We propose a mechanism for solving the “negative sign problem”—the inability to assign non-negative weights to quantum Monte Carlo configurations—for a toy model consisting of a frustrated triplet of spin-1/2 particles interacting antiferromagnetically. The introduced technique is based on the systematic grouping of the weights of the recently developed off-diagonal series expansion of the canonical partition function [Phys. Rev. E 96, 063309 (2017)PREHBM2470-004510.1103/PhysRevE.96.063309]. We show that, although the examined model is easily diagonalizable, the sign problem it encounters can nonetheless be very pronounced, and we offer a systematic mechanism to resolve it. We discuss the prospects of generalizing the suggested scheme and the steps required to extend it to more general and larger spin models.

Date

2019

Authors

Itay Hen

Journal

Physical Review E

Volume

99

Issue

3

Pages

033306

Publisher

American Physical Society