Giant Magnetic Anisotropy of Single Cobalt Atoms and Nanoparticles

  title={Giant Magnetic Anisotropy of Single Cobalt Atoms and Nanoparticles},
  author={Pietro Gambardella and Stefano Rusponi and Marco Veronese and Sarnjeet Dhesi and Cesare Grazioli and A. Dallmeyer and Ivan Cabria and R. Zeller and Peter H. Dederichs and Klaus Kern and Carmelita Carbone and Harald Brune},
  pages={1130 - 1133}
The isotropic magnetic moment of a free atom is shown to develop giant magnetic anisotropy energy due to symmetry reduction at an atomically ordered surface. Single cobalt atoms deposited onto platinum (111) are found to have a magnetic anisotropy energy of 9 millielectron volts per atom arising from the combination of unquenched orbital moments (1.1 Bohr magnetons) and strong spin-orbit coupling induced by the platinum substrate. By assembling cobalt nanoparticles containing up to 40 atoms… Expand

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