Bosonic Nevanlinna Analytic Continuation

Kosuke Nogaki; Hiroshi Shinaoka

doi:10.7566/jpsj.92.035001

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arXiv · 2305.03449

Bosonic Nevanlinna Analytic Continuation

Kosuke Nogaki·Hiroshi Shinaoka

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Abstract

Analytical continuation (AC) connects theoretical calculations and experimentally measurable quantities. The recently proposed Nevanlinna AC method is capable of accurately reproducing the sharp features of spectral functions at high frequencies while maintaining the causality of the response function. However, their use is currently limited to fermions. Here, we present an extension of this method to bosons using the hyperbolic tangent trick, allowing us to transform bosons into auxiliary fermions to which the Nevanlinna analytic continuation can be applied.

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Kosuke Nogaki, Hiroshi Shinaoka. 2023-05-05. Bosonic Nevanlinna Analytic Continuation. https://doi.org/10.7566/jpsj.92.035001

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