Skip to Main content Skip to Navigation
New interface
Journal articles

Cumulant expansion of the retarded one-electron Green function

Abstract : The cumulant expansion is a powerful approach for including correlation effects in electronic structure calculations beyond the GW approximation. However, the expansion is not generally valid, as current implementations ignore terms that mix particle and hole states and lead to partial occupation numbers of one-electron states. These limitations are corrected here using a cumulant expansion of the retarded one-electron Green’s function that includes both particle and hole contributions. The approach provides a consistent framework that improves on the GW approximation to the spectral function without additional computational effort. The method is illustrated with results for the homogeneous electron gas and comparisons to experiment and other methods.
Document type :
Journal articles
Complete list of metadata
Contributor : Gaëlle Bruant Connect in order to contact the contributor
Submitted on : Friday, February 6, 2015 - 4:40:55 PM
Last modification on : Wednesday, August 31, 2022 - 4:46:23 PM

Links full text




J. J. Kas, John J. Rehr, Lucia Reining. Cumulant expansion of the retarded one-electron Green function. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2014, 90, pp.085112. ⟨10.1103/PhysRevB.90.085112⟩. ⟨hal-01113971⟩



Record views