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Title: Laser induced spin precession in highly anisotropic granular L1{sub 0} FePt

The dynamic magnetic properties of a highly anisotropic, granular L1{sub 0} FePt thin film in magnetic fields up to 7 T are investigated using time-resolved magneto-optical Kerr effect measurements. We find that ultrashort laser pulses induce coherent spin precession in the granular FePt sample. Frequencies of spin precession up to over 400 GHz are observed, which are strongly field and temperature dependent. The high frequencies can be ascribed to the high value of the magnetocrystalline anisotropy constant K{sub u} leading to large anisotropy fields H{sub a} of up to 10.7 T at 170 K. A Gilbert damping parameter of α ∼ 0.1 was derived from the lifetimes of the oscillations.
Authors:
 [1] ;  [2] ; ;  [3] ; ; ;  [1] ; ;  [4]
  1. Radboud University Nijmegen, Institute for Molecules and Materials, Nijmegen 6525 AJ (Netherlands)
  2. (Netherlands)
  3. HGST, a Western Digital company, 3403 Yerba Buena Road, San Jose, California 95135 (United States)
  4. High Field Magnet Laboratory, Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 7, 6525 ED Nijmegen (Netherlands)
Publication Date:
OSTI Identifier:
22262606
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 15; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANISOTROPY; KERR EFFECT; LASERS; MAGNETIC FIELDS; MAGNETIC PROPERTIES; PRECESSION; SPIN; TEMPERATURE DEPENDENCE; THIN FILMS