Abstract
Zn1−x Co x O diluted magnetic semiconductor bulks were prepared by hot pressing. Mixed powders of pure ZnO and CoO were compacted under pressure of 10 MPa at the temperature of 1 073 K. Then the samples were annealed in vacuum at the temperature from 673 K to 873 K for 10 h. The crystal structure and magnetic properties of Zn1−x Co x O bulks have been investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS) was used to study chemical valence of zinc and cobalt in the samples. The results showed that Zn1−x Co x O samples had c-axis oriented wurtzite symmetry, neither cobalt or cobalt oxide phase was found in the samples if x was less than 0.15. Zn and Co existed in Zn0.9Co0.1O sample in Zn2+ and Co2+ states. The results of VSM experiment proved the room temperature ferromagnetic properties (RTFP) of Co-doped ZnO samples. The saturation magnetization and the coercivity of Zn0.9Co0.1O sample, observed in the M-H curve, were about 0.20 emu/g and 200 Oe, respectively.
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A Imamoglu, D D Awschalom, G Byrkard, et al. Quantum Information Processing Using Quantum Dot Spins and Cavity QED[J]. Phys. Rev. Lett., 1999, 83: 4 204–4 207
J K Furdyna. Diluted Magnetic Semiconductors[J]. J. Appl. Phys., 1988, 64(4): R29–R64
T Dietl, H Ohno, F Matsukura, et al. Zener Model Description of Ferromagnetism in Zinc-Blende Magnetic Semiconductors[J]. Science, 2000, 287(11): 1 019–1 022
K Sato, H K Yoshida. Ferromagnetism in a Transition Metal Atom Doped ZnO[J]. Physica E, 2001, 10: 251–255
U Kenji, Tabata H, Kawai T. Magnetic and Electric Properties of Transition-Metal-Doped ZnO Films[J]. Appl. Phys. Lett., 2001, 79(7): 953–957
C Bundesmann, N Ashkenov, M Schubert, et al. Raman Scattering in ZnO Thin Films Doped With Fe, Sb, Al, Ga, and Li[J]. Appl. Phys. Lett., 2003, 83: 1 974–1 978
G. Y Ahn, S I Park and C S Kim. Enhanced Ferromagnetic Properties of Diluted Fe Doped ZnO with Hydrogen Treatment[J]. J. Magn. Magn. Mater., 2006, 303(2): e329–e331
N R S Farley, C R Staddon, L Zhao, et al. Sol-gel Formation of Ordered Nanostructured Doped ZnO Films[J]. J. Mater. Chem., 2004, 14: 1 087–1 092
Y F Liao, H S Hsu, Y H Huang, et al. The Evidence of Cobalt Replacing Zinc Atoms in The ZnO/CoFe Diluted Magnetic Semiconductor at Room Temperature[J]. J. Magn. Magn. Mater., 2006, 304: e161–e163
K Potzger, S Q Zhou, H Reuther, et al. The Effect of Flash Lamp Annealing on Fe Implanted ZnO Single Crystals[J]. Appl. Phys. Lett., 2006, 88: 052508
H W Zhang, Z R Wei, Z Q Li, et al. Room-Temperature Ferromagnetism in Fe-Doped, Fe- and Cu-Codoped ZnO Diluted Magnetic Semiconductor[J]. Mater. Lett., 2007, 61(17): 3 605–3 607
C H Choi, S H Kim. Characterizations of Ferromagnetic Zn1−x CoxO Thin Films Grown on Al2O3 (0001) by Reactive Radio-Frequency Magnetron Sputtering Coupled with Post-Growth Annealing[J]. Thin Solid Films, 2007, 515: 2 864–2 871
J H Shim, T Hwang, S Lee, et al. Origin of Ferromagnetism in Fe- and Cu-Codoped ZnO[J]. Appl. Phys. Lett., 2005, 86: 082503
H Ohno. Making Nonmagnetic Semiconductors Ferromagnetic[J]. Science, 1998, 281: 951–955
T Yamamoto. Co-doping for the Fabrication of p-Type ZnO[J]. Thin Solid Films, 2002, 420–421: 100–106
A Kaminski, S D Sarma. Poparon Percolation in Diluted Magnetic Semiconductors[J]. Phys. Rev. Lett., 2002, 88: 24 720
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Funded by the Innovative Scientific Research Foundation of Shanghai Education Committee (No.09YZ367)
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Lin, W., Fang, N., Ouyang, C. et al. Zn1−x Co x O diluted magnetic semiconductor bulk prepared by hot pressing. J. Wuhan Univ. Technol.-Mat. Sci. Edit. 25, 527–529 (2010). https://doi.org/10.1007/s11595-010-0036-9
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DOI: https://doi.org/10.1007/s11595-010-0036-9