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DOE OSTI · 2007523

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

Carbone, Matthew R.·Fomichev, Stepan·Millis, Andrew J.·Berciu, Mona·Reichman, David R.·Sous, John
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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-SchriefferHeeger) 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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36 MATERIALS SCIENCE

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Carbone, Matthew R., Fomichev, Stepan, Millis, Andrew J., Berciu, Mona, Reichman, David R., Sous, John. 2023-10-01. The Generalized Green’s function Cluster Expansion: A Python package for simulating polarons. https://doi.org/10.21105/joss.05115

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36 MATERIALS SCIENCE↗