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arXiv · 1807.05237

irbasis: Open-source database and software for intermediate-representation basis functions of imaginary-time Green's function

Naoya Chikano·Kazuyoshi Yoshimi·Junya Otsuki·Hiroshi Shinaoka
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Abstract

The open-source library, irbasis, provides easy-to-use tools for two sets of orthogonal functions named intermediate representation (IR). The IR basis enables a compact representation of the Matsubara Green's function and efficient calculations of quantum models. The IR basis functions are defined as the solution of an integral equation whose analytical solution is not available for this moment. The library consists of a database of pre-computed high-precision numerical solutions and computational code for evaluating the functions from the database. This paper describes technical details and demonstrates how to use the library.

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Naoya Chikano, Kazuyoshi Yoshimi, Junya Otsuki, Hiroshi Shinaoka. 2018-07-13. irbasis: Open-source database and software for intermediate-representation basis functions of imaginary-time Green's function. https://doi.org/10.1016/j.cpc.2019.02.006

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