Dispersion and line shape of plasmon satellites in one, two, and three dimensions

Abstract

Using state-of-the-art many-body Green's function calculations based on the "GW plus cumulant" approach, we analyze the properties of plasmon satellites in the electron spectral function resulting from electron-plasmon interactions in one-, two-and three-dimensional systems. Specifically, we show how their dispersion relation, lineshape and linewidth are related to the properties of the constituent electrons and plasmons. To gain insight into the many-body processes giving rise to the formation of plasmon satellites, we connect the "GW plus cumulant" approach to a many-body wavefunction picture of electron-plasmon interactions and introduce the coupling-strength weighted electron-plasmon joint-density states as a powerful concept for understanding plasmon satellites.

Dynamic correlations in the highly dilute 2D electron liquid: Loss function, critical wave vector and analytic plasmon dispersion

“…Angle-resolved photoemission spectra, containing periodic crystal as well as many-electron effects, also clearly show a plasmon's fingerprint, essentially probing the single-particle propagator's 'spectral function' [13]. Pertinent work for 2DELs is found in [14][15][16].…”

Quasiparticle spectra from molecules to bulk

“…Photoemission experiments on solids reveal significant QP lifetime shortening and coupling to other collective excitations, manifested by satellite structures in the photoemission spectra [6,9,10]. The satellite structure and the QP lifetime shortening is often captured by the cumulant expansion (CE) ansatz to G 0 W 0 [6][7][8][10][11][12][13][14] .In confined systems, the QP spectrum near the bandedge is governed by the quantum confinement of electrons and holes. Higher energy, satellite-excitations are attributed to simultaneous ionization and excitation of the valence electrons ("shake-up" excitations) [13,[15][16][17][18].…”

“…Photoemission experiments on solids reveal significant QP lifetime shortening and coupling to other collective excitations, manifested by satellite structures in the photoemission spectra [6,9,10]. The satellite structure and the QP lifetime shortening is often captured by the cumulant expansion (CE) ansatz to G 0 W 0 [6][7][8][10][11][12][13][14] .…”

One-electron spectra and susceptibilities of the three-dimensional electron gas from self-consistent solutions of Hedin's equations

“…Plasmon satellites in electron gas have been studied recently using the positive-definite diagrammatic expansion for the spectral function 14 and the GW+Cumulant approach. [33][34][35][36] Both methods are implemented on real frequency axis and, thus, do not involve analytical continuation as an intermediate step in evaluating the spectral function. In these works, very good agreement with the experimental position of plasmon satellite in Na has been achieved.…”