AVS 50th International Symposium
    Magnetic Interfaces and Nanostructures Thursday Sessions
       Session MI+SC-ThM

Paper MI+SC-ThM9
Ferromagnetism in Optically Transparent Semiconducting Co Doped SnO@sub 2-d@ Films

Thursday, November 6, 2003, 11:00 am, Room 316

Session: New Spintronic Materials
Presenter: R.J. Choudhary, Univ. of Maryland
Authors: R.J. Choudhary, Univ. of Maryland
S.B. Ogale, Univ. of Maryland
S.R. Shinde, Univ. of Maryland
J.P. Buban, Univ. of Illinois at Chicago
S.E. Lofland, Rowan Univ.
S.N. Kale, Univ. of Maryland
V.N. Kulkarni, Univ. of Maryland
J. Higgins, Univ. of Maryland
C. Lanci, Rowan Univ.
J.R. Simpson, Univ. of Maryland
N.D. Browning, Univ. of Illinois at Chicago
S. Das Sarma, Univ. of Maryland
D. Drew, Univ. of Maryland
R.L. Greene, Univ. of Maryland
T. Venkatesan, Univ. of Maryland
Correspondent: Click to Email
Thin films of Co doped SnO@sub 2-d@ grown by pulsed laser deposition on single crystal sapphire substrates are examined for their magnetic, structural, electrical, magnetotransport and optical properties. The films exhibit room temperature ferromagnetism with a Curie temperature close to 650 K. In addition, the films with 5 % of Co doping exhibit a giant magnetic moment of 7.5 ± 0.5 µ@sub B@/Co. The films are highly transparent even at 27 % of Co doping. The optical bandgap shows a redshift with Co doping. Ion channeling data show a fair degree of channeling for Sn but no channeling for Co, implying Co atoms to be structurally incoherent. However, no clustering of Co can be observed in high-resolution transmission electron microscopy even up to 27 % of Co doping. The electrical resistivity shows a rapid increase with Co doping. Possible scenarios about the microscopic state of this system and the origin of ferromagnetism will be discussed.