Selective Detection of Angular-Momentum-Polarized Auger Electrons by Atomic Stereography

Fumihiko Matsui, Masayoshi Fujita, Takuya Ohta, Naoyuki Maejima, Hirosuke Matsui, Hiroaki Nishikawa, Tomohiro Matsushita, Hiroshi Daimon
2015 Physical Review Letters  
When a core level is excited by circularly polarized light, the angular momentum of light is transferred to the emitted photoelectron, which can be confirmed by the parallax shift of the forward focusing peak (FFP) direction in a stereograph of atomic arrangement. No angular momentum has been believed to be transferred to normal Auger electrons resulting from the decay process filling core hole after photoelectron ejection. We succeeded in detecting a non-negligible circular dichroism contrast
more » ... n a normal Auger electron diffraction from a nonmagnetic Cu(001) surface far off from the absorption threshold. Moreover, we detected angular-momentum-polarized Cu L 3 M 4;5 M 4;5 Auger electrons at the L 3 absorption threshold, where the excited core electron is trapped at the conduction band. From the kinetic energy dependence of the Auger electron FFP parallax shift, we found that the angular momentum is transferred to the Auger electron most effectively in the case of the 1 S 0 two-hole creation. FIG. 4 (color online). Schematic diagrams of (a) the photoemission process and (b) x-ray absorption at the L 3 edge together with (c) succeeding L 3 M 4;5 M 4;5 Auger electron emission.
doi:10.1103/physrevlett.114.015501 pmid:25615477 fatcat:i7joopyvqresbaoi6ouj2azdza