Sizeable magnetic circular dichroism of artificially precipitated Co clusters in amorphous carbon

H. S. Hsu; W. Y. Su; P. C. Chien; S. T. Kuo; S. J. Sun; P. Y. Chuang; C. H. Lee; G. H. Hwang

doi:10.1063/1.4747509

AIP Advances (Sep 2012)

Sizeable magnetic circular dichroism of artificially precipitated Co clusters in amorphous carbon

H. S. Hsu,
W. Y. Su,
P. C. Chien,
S. T. Kuo,
S. J. Sun,
P. Y. Chuang,
C. H. Lee,
G. H. Hwang

Affiliations

H. S. Hsu: Department of Applied Physics, National Pingtung University of Education, Pingtung 900, Taiwan, Republic of China
W. Y. Su: Department of Applied Physics, National Pingtung University of Education, Pingtung 900, Taiwan, Republic of China
P. C. Chien: Department of Applied Physics, National Pingtung University of Education, Pingtung 900, Taiwan, Republic of China
S. T. Kuo: Department of Applied Physics, National Pingtung University of Education, Pingtung 900, Taiwan, Republic of China
S. J. Sun: Department of Applied Physics, National University of Kaohsiung, Kaohsiung 811, Taiwan, Republic of China
P. Y. Chuang: Department of Engineering and System Science, National Tsing-Hua University, HsinChu 300, Taiwan, Republic of China
C. H. Lee: Department of Engineering and System Science, National Tsing-Hua University, HsinChu 300, Taiwan, Republic of China
G. H. Hwang: Department of Physics, National Kaohsiung Normal University, Kaohsiung 824, Taiwan, Republic of China

DOI: https://doi.org/10.1063/1.4747509
Journal volume & issue: Vol. 2, no. 3
pp. 032142 – 032142-6

Abstract

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This study examines sizeable magnetic circular dichroism (MCD) in Co(20%)-doped amorphous carbon (a-C) films. While as-grown films exhibit a non-detectable MCD signal, films that undergo rapid thermal annealing (RTA) at 600°C in a vacuum yield broad MCD spectra with a large amplitude of ∼3.9 × 104 deg/cm in saturation field 0.78 T at the σ-σ* gap transition (∼5.5 eV). In such films after RTA, the metastable Co-C bonding is decomposed and suitable Co nanoparticles/a-C interfaces are thus formed. Our results indicate that the large change in MCD is contributed from Co nanoparticles and associated with the spin-dependent electronic structure at the Co/a-C interfaces.

Published in AIP Advances

ISSN: 2158-3226 (Online)
Publisher: AIP Publishing LLC
Country of publisher: United States
LCC subjects: Science: Physics
Website: http://aipadvances.aip.org/

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