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Magnetic Nanoparticle Aggregation States in Ag100-xFex Cosputtered Granular Films Investigated by Magnetic and Magnetotransport Measurements

Published online by Cambridge University Press:  01 February 2011

Paolo Allia
Affiliation:
Physics Department, Politecnico di Torino, Corso Duca degli Abruzzi 24, I- 1029 Torino, Italy
Federica Celegato
Affiliation:
Physics Department, Politecnico di Torino, Corso Duca degli Abruzzi 24, I- 1029 Torino, Italy
Marco Coisson
Affiliation:
Materials Department, IEN Galileo Ferraris, Strada delle Cacce 91, I-10135 Torino, Italy
Paola Tiberto
Affiliation:
Materials Department, IEN Galileo Ferraris, Strada delle Cacce 91, I-10135 Torino, Italy
Franco Vinai
Affiliation:
Materials Department, IEN Galileo Ferraris, Strada delle Cacce 91, I-10135 Torino, Italy
Federico Spizzo
Affiliation:
Physics Department, Universitä di Ferrara, Via Paradiso 12, I-44100 Ferrara, Italy
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Abstract

Magnetoresistance and.magnetization measurements have been performed on nanogranular, cosputtered Ag100-xFex films (x= 10 to 30) in the 4 K – 300 K temperature interval. The analysis reveals that the films with x ≤ 14 are interacting superparamagnets, characterized by a magnetic correlation length of the order of the electronic mean free path λ. Films with x ≥ 26 behave as concentrated magnets with strong competing interactions among magnetic moments (frustrated ferromagnets) and magnetic correlation length much larger than λ.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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References

[1] Berkowitz, A. E., Mitchell, J. R., Carey, M. J., Young, A. P., Zhang, S., Spada, F. E., Parker, F. T., Hutten, A., and Thomas, G., Phys. Rev. B 68, 3745 (1992).Google Scholar
[2] Daughton, J. M., J. Magn. Magn. Mater. 192, 334 (1999).Google Scholar
[3] Xiao, J. Q., Jiang, J. S., and Chien, C.L., Phys Rev. Lett. 68, 3749 (1992).Google Scholar
[4] Allia, P., Coisson, M., Moya, J., Selvaggini, V., Tiberto, P., and Vinai, F., Phys. Rev. B67, 174412 (2003).Google Scholar
[5] Allia, P., Knobel, M., Tiberto, P., and Vinai, F., Phys. Rev. B 52, 15398 (1995).Google Scholar
[6] Allia, P., Coisson, M., Re, A. Da, Celegato, F., Spizzo, F., Tiberto, P., and Vinai, F., phys. stat. sol. (c) 1, 3406 (2004).Google Scholar
[7] Allia, P., Coisson, M., Tiberto, P., Vinai, F., Knobel, M., Novak, M.A., and Nunes, W.C., Phys. Rev. B64, 144420 (2001).Google Scholar
[8] Spizzo, F., Angeli, E., Bisero, D., Re, A. Da, Ronconi, F., Vavassori, P., Bergenti, I., Deriu, A., and Hoell, A., J. Appl. Cryst. 36, 826 (2003).Google Scholar
[9] Wang, J.Q. and Xiao, G., Phys. Rev. B49, 3982 (1994)Google Scholar