Energy- and k -resolved mapping of the magnetic circular dichroism in threshold photoemission from Co films on Pt(111)
Staab M, Kutnyakhov D, Wallauer R, Chernov S, Medjanik K, Elmers HJ, Klaeui M, Schoenhense G (2017)
Publication Type: Journal article
Publication year: 2017
Journal
Book Volume: 95
Article Number: 165437
Journal Issue: 16
DOI: 10.1103/PhysRevB.95.165437
Abstract
The magnetic circular dichroism in threshold photoemission (TPMCD) for perpendicularly magnetized fcc Co films on Pt(111) has been revisited. A complete mapping of the spectral function I(EB,kx,ky) (binding energy EB, momentum parallel to surface kx, ky) and the corresponding TPMCD asymmetry distribution AMCD(EB,kx,ky) has been performed for one-photon and two-photon photoemission using time-of-flight momentum microscopy. The experimental results allow distinguishing direct from indirect transitions. The measurements reveal clear band features of direct transitions from bulk bands that show a nontrivial asymmetry pattern. A significant homogeneous background with substantial asymmetry stemming from indirect transitions superposes direct transitions. Two-photon photoemission reveals enhanced emission intensity via an image potential state, acting as intermediate state. The image potential state enhances not only intensity but also asymmetry. The present results demonstrate that two-photon photoemission is a powerful method for mapping the spin-polarized unoccupied band structures and points out pathways for applying TPMCD as a contrast mechanism for various classes of magnetic materials.
Involved external institutions
Germany (DE)How to cite
APA:
Staab, M., Kutnyakhov, D., Wallauer, R., Chernov, S., Medjanik, K., Elmers, H.J.,... Schoenhense, G. (2017). Energy- and k -resolved mapping of the magnetic circular dichroism in threshold photoemission from Co films on Pt(111). Physical Review B, 95(16). https://doi.org/10.1103/PhysRevB.95.165437
MLA:
Staab, Maximilian, et al. "Energy- and k -resolved mapping of the magnetic circular dichroism in threshold photoemission from Co films on Pt(111)." Physical Review B 95.16 (2017).
BibTeX: Download