title: Breaking the theoretical scaling limit for predicting quasiparticle energies: the stochastic GW approach.
abstract: We develop a formalism to calculate the quasiparticle energy within the GW many-body perturbation correction to the density functional theory. The occupied and virtual orbitals of the Kohn-Sham Hamiltonian are replaced by stochastic orbitals used to evaluate the Green function G, the polarization potential W, and, thereby, the GW self-energy. The stochastic GW (sGW) formalism relies on novel theoretical concepts such as stochastic time-dependent Hartree propagation, stochastic matrix compression, and spatial or temporal stochastic decoupling techniques. Beyond the theoretical interest, the formalism enables linear scaling GW calculations breaking the theoretical scaling limit for GW as well as circumventing the need for energy cutoff approximations. We illustrate the method for silicon nanocrystals of varying sizes with N_{e}>3000 electrons.
authors.affiliation: Department of Chemistry, University of California at Los Angeles, California 90095, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Neuhauser
authors.affiliation: Department of Chemistry, University of California at Los Angeles, California 90095, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Department of Chemistry, University of California at Los Angeles, California 90095, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Arntsen
authors.affiliation: Department of Chemistry, University of California at Los Angeles, California 90095, USA.
authors.forename: Cyrus
authors.initials: C
authors.lastname: Karshenas
authors.affiliation: School of Chemistry, The Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Eran
authors.initials: E
authors.lastname: Rabani
authors.affiliation: Fritz Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
authors.forename: Roi
authors.initials: R
authors.lastname: Baer