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Self-Assembled Structures of Gas-Phase Prepared FePt Nanoparticles

Published online by Cambridge University Press:  15 March 2011

Bernd Rellinghaus
Affiliation:
Experimentelle Tieftemperaturphysik and Sonderforschungsbereich 445, Gerhard-Mercator-Universität, D-47048 Duisburg, Germany
Sonja Stappert
Affiliation:
Experimentelle Tieftemperaturphysik and Sonderforschungsbereich 445, Gerhard-Mercator-Universität, D-47048 Duisburg, Germany
Mehmet Acet
Affiliation:
Experimentelle Tieftemperaturphysik and Sonderforschungsbereich 445, Gerhard-Mercator-Universität, D-47048 Duisburg, Germany
Eberhard F. Wassermann
Affiliation:
Experimentelle Tieftemperaturphysik and Sonderforschungsbereich 445, Gerhard-Mercator-Universität, D-47048 Duisburg, Germany
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Abstract

We report on a non-lithographic method for the preparation of self-assembled FePt nanoparticles via inert-gas condensation. Prior to deposition the particles can be sintered in flight at temperatures as high as TS = 1273 K. Whereas un-sintered particles have irregular shapes, particles sintered at elevated temperatures TS ≥ 793 K show a regular faceting. (High resolution) transmission electron microscopy ((HR)TEM) shows that these regularly faceted particles are of icosahedral structure. When being deposited onto amorphous carbon films, the gas-phase sintered particles are found to have a high mobility. In particular, for the high-temperature sintered FePt nanoparticles, we observe that this mobility leads to the formation of particle arrays with hexagonal close-packed arrangements. Within these ordered patches, the particles are separated from one another. Analytical investigations using energy filtered TEM (EFTEM) show that a carbon layer is formed between the particles. Magnetization analyses give results showing that the gas-phase sintered particles are superparamagnetic at room temperature with a blocking temperature of TB = 49K.

Type
Research Article
Copyright
Copyright © Materials Research Society 2002

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References

1. Fullerton, E.E., Margulies, D.T., Schabes, M.E., Carey, M., Gurney, B., Moser, A., Best, M., Zeltzer, G., Rubin, K., Rosen, H., Doerner, M., Appl. Phys. Lett. 77, 3806 (2000)Google Scholar
2. Smyth, J.F., Schultz, S., Fredkin, D.R., Kern, D.P., Rishton, S.A., Schmid, H., Cali, M., and Koehler, T.R.; Appl, J., Phys. 69, 5262 (1991);R. M. H. New, R. F. W. Pease, und R. L. White; J. Vac. Sci. Technol. B12, 3196 (1994).Google Scholar
3. Garvin, H.L., Garmire, E., Somekh, S., Stoll, H., and Yariv, A., Appl.Optics, 12, 455 (1973); D.C. Flanders, H.I. Smith, H.W. Lehmann, R Widmer, and D.C. Shaver, Appl. Phys. Lett. 32, 112 (1978).Google Scholar
4. Lohau, J., Moser, A., Rettner, C.T., Best, M.E., and Terris, B.D., Appl. Phys. Lett. 78, 990992 (2001).Google Scholar
5. Chou, S.Y., Krauss, P.R., Renstrom, P.J., J. Vac. Sci. Technol. B 14, 41294133 (1996).Google Scholar
6. Ochiai, Y., Baba, M., Watanabe, H., and Matsui, S., Jpn. J. Appl. Phys. 30, 32663271 (1991).Google Scholar
7. Carl, A., Kirsch, S., Lohau, J., Weinforth, H., and Wassermann, E.F., IEEE Trans. Mag. 35, 31063111 (1999).Google Scholar
8. Zankovych, S., Hoffmann, T., Seekamp, J., Bruch, J.-U., Torres, C.M. Sotomayor, Nanotechnology 12, 9195 (2001); A. Tilke, R.H. Blick, and H. Lorentz, J. Appl. Phys. 90, 942-946 (2001).Google Scholar
9. Murray, C.B., Kagan, C.R., and Bawendi, M.G., Science 270, 13351338 (1995).Google Scholar
10. Sun, S., Murray, C.B., Weller, D., Folks, L., and Moser, A., Science 287, 19891992 (2000).Google Scholar
11. Bean, C.P., Livingston, J.D., J. Appl. Phys. 30, 120S129S (1959); D. Weller and A. Moser, IEEE Trans. Mag. 35, 4423-4439 (1999).Google Scholar
12.See e.g.: Sellmyer, D.J., Zheng, M., and Skomski, R., J. Phys.: Condens. Matter 13, R433–R460 (2001); and references therein.Google Scholar
13. Weller, D., Moser, A., Folks, L., Best, M.E., Lee, W., Toney, M.F., Schwickert, M., Thiele, J.-U., and Doerner, M.F., IEEE Trans. Mag. 36, 1015 (2000).Google Scholar
14. Stappert, S., Rellinghaus, B., Acet, M., and Wassermann, E.F., Mat. Res. Soc. Proc. 704, Nanoparticulate Materials, submitted.Google Scholar
15. Cullity, B.D., “Introduction To Magnetic Materials” (Addison-Wesley, 1972), pp. 410.Google Scholar
16.See e.g.: Kruis, F.E., Nielsch, K., Fissan, H., Rellinghaus, B., and Wassermann, E.F., Appl. Phys. Lett. 73, 547549 (1998); and references therein.Google Scholar
17. Fan, X., Dickey, E.C., Eklund, P., Williams, K., Grigorian, L., Puretzky, A., Geohegan, D., Buczko, R., Pantelides, S.T., and Pennycook, S.J., Mat. Res. Soc. Prc. 593, 129134 (2000), Warrendale, PA, USA; M. Andersson, P. Alberius-Henning, K. Jansson, and N. Nygren, J. Mater. Res. 15, 1822-1827 (2000); P.E. Andersson and N.M. Rodrigez, J. Mater. Res. 14, 2912-2921 (1999).Google Scholar
18. Wilke, S., Natoli, V., and Cohen, M.H., J. Chem. Phys. 112, 99869995 (2000); S. Völkening, K. Bedürftig, K. Jacobi, J. Wintterlin, and G. Ertl, Phys. Rev. Lett. 83, 2672-2675 (1999).Google Scholar
19. Rolison, D.R., in “Nanoparticles: Synthesis, Properties and Applications“, ed. by Edelstein, A.S. and Cammarata, R.C., (Institute of Physics Publishing, London, UK, 1996), pp. 305; and references therein.Google Scholar
20. Flagan, R.C. and Lunden, M.M., Mater. Sci. Eng. A204, 113124 (1995).Google Scholar
21. Stahl, B., Gajbiye, N.S., Wilde, G., Kramer, D., Ellrich, J., Ghafari, M., Hahn, H., Gleiter, H., Weißmüller, J., Würschum, R., and Schlossmacher, P., preprint (2001).Google Scholar
22. Ahmadi, T.S., Wang, Z.L., Green, T.C., Henglein, A., and El-Sayed, M.A., Science 272, 19241926 (1996); J.M. Petroski, Z.L. Wang, T.C. Green, and M.A. El-Sayed, J. Phys. Chem. B 102, 3316-3329 (1998).Google Scholar
23. Olynick, D.L., Gibson, J.M., and Averback, R.S., Appl. Phys. Lett. 68, 343345 (1995).Google Scholar