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arXiv · 1811.03027

Resolution of the Sign Problem for a Frustrated Triplet of Spins

Itay Hen
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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)]. We show that while 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 generalization of the suggested scheme and the steps required to extend it to more general and larger spin models.

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BibTeXRIS

Itay Hen. 2019-03-08. Resolution of the Sign Problem for a Frustrated Triplet of Spins. https://doi.org/10.1103/physreve.99.033306

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