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Title: Description of quasiparticle and satellite properties via cumulant expansions of the retarded one-particle Green's function

A cumulant-based GW approximation for the retarded one-particle Green's function is proposed, motivated by an exact relation between the improper Dyson self-energy and the cumulant generating function. We explore qualitative aspects of this method within a simple one-electron independent phonon model, where it is seen that the method preserves the energy moment of the spectral weight while also reproducing the exact Green's function in the weak-coupling limit. For the three-dimensional electron gas, this method predicts multiple satellites at the bottom of the band, albeit with inaccurate peak spacing. But, its quasiparticle properties and correlation energies are more accurate than both previous cumulant methods and standard G0W0. These results point to features that may be exploited within the framework of cumulant-based methods and suggest promising directions for future exploration and improvements of cumulant-based GW approaches.
 [1] ;  [2] ;  [1]
  1. Columbia Univ., New York, NY (United States). Dept. of Chemistry
  2. Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials
Publication Date:
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 2469-9950; PRBMDO; R&D Project: 16068; KC0403020
Grant/Contract Number:
SC00112704; SC0012704
Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 94; Journal Issue: 8; Journal ID: ISSN 2469-9950
American Physical Society (APS)
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States