We extend the three-layer model for energy loss calculation to include many-body effects in an ab initio framework. The electron energy loss spectrum of the C(100)2x1 surface is calculated and compared with the existing experimental results. We show how many-body effects, namely self-energy, local-fields, and electron-hole interaction, deeply influence the dielectric response and how their inclusion is essential to have good agreement with the experiment. A strong anisotropic behavior of local-field effects on the dielectric response has been observed, while the inclusion of the electron-hole attractive interaction produces a surface-state exciton with binding energy of about 1 eV, confirming a recent theoretical-experimental study of the optical spectra of this surface.
Palummo, M., Pulci, O., Marini, A., Reining, L., Del Sole, R. (2006). Ab initio calculation of many-body effects on the EEL spectrum of the C(100) surface. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 74(23) [10.1103/PhysRevB.74.235431].
Ab initio calculation of many-body effects on the EEL spectrum of the C(100) surface
PALUMMO, MAURIZIA;PULCI, OLIVIA;
2006-01-01
Abstract
We extend the three-layer model for energy loss calculation to include many-body effects in an ab initio framework. The electron energy loss spectrum of the C(100)2x1 surface is calculated and compared with the existing experimental results. We show how many-body effects, namely self-energy, local-fields, and electron-hole interaction, deeply influence the dielectric response and how their inclusion is essential to have good agreement with the experiment. A strong anisotropic behavior of local-field effects on the dielectric response has been observed, while the inclusion of the electron-hole attractive interaction produces a surface-state exciton with binding energy of about 1 eV, confirming a recent theoretical-experimental study of the optical spectra of this surface.Questo articolo è pubblicato sotto una Licenza Licenza Creative Commons
