Exploring 4f collective magnetic signatures in a Holmium coordinated network at the 2D limit

The goal of this proposal is the determination of the spin and orbital magnetic moment, as well as the magnetic anisotropy energy (MAE) of a periodic array of Holmium (Ho) atoms coordinating an extended, atom-thick network grown on Au(111). This metal-organic coordination network (MOCN) is realized by combining 9,10 dicyanoanthracene (DCA) molecules and single Ho atoms. The resulting 2D mixed honeycomb-kagomé lattice is weakly interacting with the Au(111) support (Figure 1a). The success in this proposal is guaranteed from the well-characterized sample preparations we have already achieved in our home lab using STM, STS, LEED, XPS and ARPES, as well as from our previous experience with DCA-Fe 2D-MOCN (ref.1) and HoAu2 surface alloys (ref.2) in BOREAS from proposals ID2020024265 and ID2021095444. The highly ordered 2D-MOCNs achieved with DCA molecules considerably differ from single molecule magnets and exhibit few defects, which allows to obtain clean 4f spectroscopic signals, essential for understanding the resulting spin and orbital magnetic moments of the coordinated Ho atoms.