The sign of the overlap of HFB wave functions

TL;DR

This paper presents a method for accurately and efficiently determining the sign of the overlap between two general Hartree-Fock-Bogoliubov (HFB) wave functions, with implications for evaluating traces of density operators.

Contribution

It introduces a novel approach to compute the sign of HFB wave function overlaps, improving accuracy and efficiency over previous methods.

Findings

Method reliably determines the sign of HFB overlaps.

Approach can be extended to trace evaluations of density operators.

Enhances computational techniques in quantum many-body physics.

Abstract

The problem of how to compute accurately and efficiently the sign of the overlap between two general HFB wave functions is addressed. The results obtained can easily be extrapolated to the evaluation of the sign of the trace of a density operator exponential of one body operators.