Origin of perpendicular anisotropy in Fe atoms

Origin of Perpendicular Magnetic Anisotropy and Large Orbital Moment in Fe Atoms on MgO.

S. Baumann, F. Donati, S. Stepanow, S. Rusponi, W. Paul, S. Gangopadhyay, I. G. Rau, G. E. Pacchioni, L. Gragnaniello, M. Pivetta, J. Dreiser, C. Piamonteze, C. P. Lutz, R. M. Macfarlane, B. A. Jones, P. Gambardella, A. J. Heinrich, and H. Brune

Phys. Rev. Lett. 115, 237202 (2015)

(a) STM image of two Fe atoms on a ML MgO(100) grown on Ag(100) (4  nm×4  nm, tunnel current It=5  pA, tunnel voltage Vt=100  mV). (b) Side view of DFT-calculated binding geometry and charge density [color scale, 1e/(au)3; Fe, green; O, red; Mg, blue). (Middle sketch) Top view ball model of the binding geometry. (c) Oblique view of DFT-calculated valence electron spin density contours (positive spin polarization, red; negative, blue).