Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 13: Magnetic Surface Excitations
O 13.2: Talk
Monday, March 7, 2016, 15:30–15:45, S052
Origin of inelastic excitations in rare-earth based metal-organic complexes — •Daniela Rolf1, Matthias Bernien1, Paul Stoll1, Qingyu Xu1, Fabian Nickel1, Claudia Hartmann1, Tobias R. Umbach1, Jens Kopprasch1, Janina N. Ladenthin1, Enrico Schierle2, Eugen Weschke2, Constantin Czekelius3, Wolfgang Kuch1, and Katharina J. Franke1 — 1Freie Universität Berlin, Germany — 2Helmholtz-Zentrum Berlin für Materialien und Energie, Germany — 3Heinrich-Heine-Universität Düsseldorf, Germany
Rare-earth atoms with a partially filled f shell exhibit interesting magnetic properties due to their large magnetic anisotropy. Within the Dysprosium-tris(1,1,1-trifluoro-4-(2-thienyl)-2,4-butanedionate) (Dy(tta)3) complex, Dy exhibits a total angular momentum of J = 15/2 with anisotropy-split MJ levels. Employing low-temperature STM we show that deposition of Dy(tta)3 on a Au(111) surface leads to densely packed self-assembled islands. XMCD measurements on Dy(tta)3 show a sizeable magnetic anisotropy. dI/dV-spectra on these molecules exhibit symmetric steps at ±7.6 meV, which correspond to an inelastic excitation. To identify the origin of this feature unambiguously, we compare to spectra taken on the isostructural Gd(tta)3, showing an inelastic step at a similar energy. As Gd3+ has a half-filled f shell, it is not expected to show any magnetic anisotropy. Hence, we conclude that the inelastic steps do not arise due to transitions between the anisotropy-split spin states, but can be explained by the excitation of molecular vibrations.