SKM 2023 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 30: 2D Materials I: Electronic Structure
O 30.3: Vortrag
Dienstag, 28. März 2023, 11:00–11:15, GER 37
Circular dichroism in valence band photoemission from CrGeTe3 — •Honey Boban1, Mohammed Qahosh1, Xiao Hou1, Magdalena Szczepanik2, Ewa Partyka-Jankowska2, Tomasz Sobol2, Tom G Saunderson3,4, Yuriy Mokrousov3,4, Mathias Kläui3, Claus Michael Schneider1, and Lukasz Plucinski1 — 1PGI-6, FZ Jülich, Germany — 2NSRC SOLARIS, Poland — 3University of Mainz, Germany — 4PGI-1, FZ Jülich, Germany
CrGeTe3(CGT) is a layered ferromagnetic semiconductor with a bulk Curie temperature (Tc) of 63K[1] and an indirect bandgap of 0.4eV[2]. A previous band structure mapping study of CGT[1] revealed band renormalizations below and above Tc and resonance enhancements at the Cr 3p absorption edge. CGT contains large Te atoms (Z=52), therefore spin-momentum locked splittings, Weyl nodes, and anticrossings are expected due to a combination of ferromagnetism and spin-orbit coupling, as well as the related Berry curvature physics. We performed light-polarization-dependent and temperature-dependent angle-resolved photoemission (ARPES) measurements on surfaces of bulk CGT. We have observed renormalizations in the dichroic ARPES maps below and above Tc, which could be indirectly related to magnetic ordering, even though our technique most likely averages spin-up and spin-down domains. Circular dichroic ARPES maps contain an intrinsic contribution due to the orbital angular momentum through dipole selection rules and an extrinsic contribution due to the experimental geometry. Our current work focuses on disentangling the two effects. Ref: [1] PRB 101, 205125(2020), [2] PRB 98, 125127(2018)