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arXiv · 2210.12260

The Generalized Green's function Cluster Expansion: A Python package for simulating polarons

Matthew R. Carbone·Stepan Fomichev·Andrew J. Millis·Mona Berciu·David R. Reichman·John Sous
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Abstract

We present an efficient implementation of the Generalized Green's function Cluster Expansion (GGCE), which is a new method for computing the ground-state properties and dynamics of polarons (single electrons coupled to lattice vibrations) in model electron-phonon systems. The GGCE works at arbitrary temperature and is well suited for a variety of electron-phonon couplings, including, but not limited to, site and bond Holstein and Peierls (Su-Schrieffer-Heeger) couplings, and couplings to multiple phonon modes with different energy scales and coupling strengths. Quick calculations can be performed efficiently on a laptop using solvers from NumPy and SciPy, or in parallel at scale using the PETSc sparse linear solver engine.

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Matthew R. Carbone, Stepan Fomichev, Andrew J. Millis, Mona Berciu, David R. Reichman, John Sous. 2022-10-21. The Generalized Green's function Cluster Expansion: A Python package for simulating polarons. https://doi.org/10.21105/joss.05115

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