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Updated: Jul 14, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Outstanding spin-orbit-activated interchannel coupling in the Cs and Ba 3d photoemission
T Richter1, E Heinecke, P Zimmermann
1Institut für Optik und Atomare Physik, Technische Universität Berlin, Berlin, Germany.
Abstract:
Partial 3d5/2 photoionization cross sections of atomic Cs and Ba as well as the asymmetry parameter beta of the angular distribution of the Cs 3d5/2 photoelectrons were investigated near the threshold of the 3d3/2 channel at about 750 eV and 800 eV, respectively. Strong electron correlations, in particular, the spin-orbit activated interchannel coupling between the 3d5/2 and 3d3/2 channels, govern the observed spectra. The most striking effect was found for beta5/2 of Cs with a dramatic increase from beta=1.0 to beta=1.5 in the energy region where the mixing between both channels causes a pronounced minimum in the partial 3d5/2 cross section. This result indicates the decisive influence of the interference term on the asymmetry parameter beta with its dependence on the phase difference between the outgoing p and f waves.
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