Stoll, P.; Bernien, M.; Rolf, D.; Nickel, F.; Xu, Q.; Hartmann, C.; Umbach, T.R.; Kopprasch, J.; Ladenthin, J.N.; Schierle, E.; Weschke, E.; Czekelius, C.; Kuch, W.; Franke, K.J.: Magnetic anisotropy in surface-supported single-ion lanthanide complexes. Physical Review B 94 (2016), p. 224426/1-13
10.1103/PhysRevB.94.224426
Open Accesn Version

Abstract:
Single-ion lanthanide-organic complexes can provide stable magnetic moments with well-defined orientation for spintronic applications on the atomic level. Here, we show by a combined experimental approach of scanning tunneling microscopy and x-ray absorption spectroscopy that dysprosium-tris(1,1,1-trifluoro-4-(2-thienyl)-2,4- butanedionate) (Dy(tta)3) complexes deposited on a Au(111) surface undergo a molecular distortion, resulting in distinct crystal field symmetry imposed on the Dy ion. This leads to an easy-axis magnetization direction in the ligand plane. Furthermore, we show that tunneling electrons hardly couple to the spin excitations, which we ascribe to the shielded nature of the 4f electrons.