The origin of narrowing of the Si 2p coincidence photoelectron spectroscopy main line of Si(1Â 0Â 0) surface

The Si 2p photoelectron spectroscopy (PES) main line of Si(1 0 0) surface measured in coincidence with the singles (noncoincidence) Si L2,3-VV Auger-electron spectroscopy (AES) elastic peak is calculated. The agreement with the experiment is good. The present work is the first many-body calculation of the experimental coincidence PES spectrum of solid surface. The narrowing of the coincidence Si 2p PES main line compared to the singles one is due to the mechanism inherent in the coincidence PES. The inherent mechanism is explained by a many-body theory by which photoemission and Auger-electron emission are treated on the same footing.

► The Si 2p coincidence photoelectron spectroscopy (PES) main line of Si(1 0 0) is calculated. ► The PES main line shows an asymmetric line shape change compared to the singles one. ► The narrowing of the coincidence Si 2p PES main line is well reproduced. ► The inherent mechanism of APECS is explained by a many-body theory.