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arXiv · 2105.06806

EDIpack: A parallel exact diagonalization package for quantum impurity problems

A. Amaricci·L. Crippa·A. Scazzola·F. Petocchi·G. Mazza·L. de Medici·M. Capone
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Abstract

We present EDIpack, an exact diagonalization package to solve generic quantum impurity problems. The algorithm includes a generalization of the look-up method introduced in [Lin, Gubernatis Comput. Phys., 7 (4) (1993), 400] and enables a massively parallel execution of the matrix-vector linear operations required by Lanczos and Arnoldi algorithms. We show that a suitable Fock basis organization is crucial to optimize the inter-processors communication in a distributed memory setup and to reach sub-linear scaling in sufficiently large systems. We discuss the algorithm in details indicating how to deal with multiple orbitals and electron-phonon coupling. Finally, we outline the download, installation and functioning of the package.

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A. Amaricci, L. Crippa, A. Scazzola, F. Petocchi, G. Mazza, L. de Medici, M. Capone. 2021-05-13. EDIpack: A parallel exact diagonalization package for quantum impurity problems. https://doi.org/10.1016/j.cpc.2021.108261

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