Resolution of the Sign Problem for a Frustrated Triplet of Spins

Understand

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)].