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We report on angle-resolved photoemission studies of the electronic pi states of high-quality epitaxial graphene layers on a Ni(111) surface. In this system the electron binding energy of the pi states shows a strong dependence on the magnetization reversal of the Ni film. The observed extraordinarily large energy shift up to 225 meV of the graphene-derived(More)
Regularly sized Ni nanoclusters (NCs) have been grown on a graphene Moire on Rh(J 11). Using scanning tunneling microscopy, we determine that initial growth of Ni at 150 K leads to preferential nucleation of monodispersed NCs at specific sites of the Moire superstructure. However, a defined long-range ordering of NCs with increasing coverage is not(More)
Here we report a photoemission study of the Fe intercalation underneath a graphene layer on Ni͑111͒. The process of intercalation was monitored by means of x-ray photoemission of corresponding core levels as well as ultraviolet photoemission of the graphene-derived ␲ states in the valence band. Thin fcc Fe layers ͑2–5 ML thickness͒ at the interface between(More)
We present a detailed study of the spin-dependent electronic structure of thin epitaxial magnetite films of different crystallographic orientations. Using spin- and angle-resolved photoelectron spectroscopy at room temperature, we determine for epitaxial Fe(3)O(4)(111) films a maximum spin polarization value of -(80 ± 5)% near E(F). The spin-resolved(More)
Magnetic domains and domain walls in epitaxial Fe 3 O 4 (100) elements (rings and wires) are imaged using magnetic force microscopy and photoemission electron microscopy. We show that the interplay between the four-fold magnetocrystalline anisotropy and the shape determines the equilibrium domain structure. Domain walls with a characteristic zigzag(More)
This paper presents our work on the investigation of the surface structure and the electronic and magnetic properties of the graphene layer on the lattice-matched surface of a ferromagnetic material, Ni(111). Scanning tunneling microscopy imaging shows that perfectly ordered epitaxial graphene layers can be prepared by elevated temperature decomposition of(More)
In situ prepared Fe 3 O 4 ͑100͒ thin films were studied by means of scanning tunneling microscopy ͑STM͒ and spin-polarized photoelectron spectroscopy ͑SP-PES͒. The atomically resolved ͑ ͱ 2 ϫ ͱ 2͒R45° wavelike surface atomic structure observed by STM is explained based on density functional theory ͑DFT͒ and ab initio atomistic thermodynamics calculations as(More)
Realization of graphene moiré superstructures on the surface of 4d and 5d transition metals offers templates with periodically modulated electron density, which is responsible for a number of fascinating effects, including the formation of quantum dots and the site selective adsorption of organic molecules or metal clusters on graphene. Here, applying the(More)
We use in situ scanning tunneling microscopy (STM) to investigate intercalation of the ferromagnetic 3d metals Ni and Fe underneath a graphene monolayer on Rh(111). Upon thermal annealing of graphene/Rh(111) with the deposited metal on top, we observe the formation of epitaxial monatomic nanoislands grown pseudomorphically on Rh(111) and covered by(More)