Berlin 2012 – wissenschaftliches Programm
MA 37.11: Vortrag
Donnerstag, 29. März 2012, 12:15–12:30, EB 301
Detecting spin excitation of rare-earth atoms and clusters on metallic surfaces — •Toshio Miyamachi1, Tobias Schuh1, Stefan Gerstl1, Arthur Ernst2, and Wulf Wulfhekel1 — 1Physikalisches Institut, Karlsruher Institut für Technologie, Germany — 2Max-Planck-Institut für Mikrostrukturphysik, Halle, Germany
At the heart of the stability of magnetic bits in information storage is a magnetic anisotropy energy (MAE) and magnetization dynamics. Recent inelastic tunneling spectroscopy (ITS) studies have revealed that the spin states of 3d transition metal atoms and clusters on metallic substrates have extremely short lifetimes of the order of femtosecond due to strong hybridization of 3d states and substrates . To reduce the influence of substrates from atoms and clusters, 4f rare-earth Gd atoms and clusters on Pt(111) and Cu(111) were studied with ITS. Since the 4f states are inner orbitals, the hybridization with substrates could be decreased. In addition, as the relativistic spin orbit interaction plays a crucial role for the MAE, 4f atoms with larger spin and orbital momenta could show larger MAEs than 3d atoms . Obtained results show that the spin excitation of 4f states can be accessed with ITS, and that giant magnetic anisotropies and lifetimes of the excited states of Gd are nearly independent of supporting substrate or size of the cluster, reflecting the strongly localized character of 4f electrons in Gd atoms and clusters.
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 T. Schuh et al., Phys. Rev. B. 84, 104401 (2011)