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arXiv · 2302.10476

Nevanlinna.jl: A Julia implementation of Nevanlinna analytic continuation

Kosuke Nogaki·Jiani Fei·Emanuel Gull·Hiroshi Shinaoka
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Abstract

We introduce a Julia implementation of the recently proposed Nevanlinna analytic continuation method. The method is based on Nevanlinna interpolants and, by construction, preserves the causality of a response function. For theoretical calculations without statistical noise, this continuation method is a powerful tool to extract real-frequency information from numerical input data on the Matsubara axis. This method has been applied to first-principles calculations of correlated materials. This paper presents its efficient and full-featured open-source implementation of the method including the Hamburger moment problem and smoothing.

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Kosuke Nogaki, Jiani Fei, Emanuel Gull, Hiroshi Shinaoka. 2023-02-21. Nevanlinna.jl: A Julia implementation of Nevanlinna analytic continuation. https://doi.org/10.21468/scipostphyscodeb.19

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