Abstract
A 59Co NMR study has been carried out on several series of co-evaporated Co1-xFex thin-film alloys prepared on MgO (001), GaAs (100), and GaAs (110) substrates at deposition temperatures between 175°C and 500°C. The sample thicknesses varied between 100 Å and 1000 Å and the alloy concentrations were in the range 0:1 < x < 0:3. X-ray diffraction and NMR show that the stability limits of the bcc phase in CoFe alloys is shifted from the x = 0:25 observed in the bulk alloys down to about x = 0:11 in thin films. For x = 0:27 and at the deposition temperature of 500°C, a new ordered phase has been stabilised where Co has two Fe atoms only in its first coordination shell. Other samples, grown at lower temperatures, also exhibit an exotic chemical short range order (CSRO) where Co coordinations with zero and two Fe neighbours dominate. A mixture of bcc Co (and not fcc Co as in the bulk alloys) and unknown ordered bcc intermetallics can account for the observed CSRO. Theoretical ground-state phases for the bcc lattice are considered in order to explain the observations.
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Senda, M., Nagai, Y.: Appl. Phys. Lett. 52, 672 (1988)
Gutierrez, C.J., Krebs, J.J., Prinz, G.A.: Appl. Phys. Lett. 61, 2476 (1992)
Gutierrez, C.J., Prinz, G.A., Krebs, J.J., Filipkowski, M.E., Harris, V.G., Elam, W.T.: J. Magn. Magn. Mater. 126, 232 (1993)
Kubaschewski, O.: Iron binary phase diagrams, p. 27, Berlin, Heidelberg, New York: Springer 1982
Mühge, Th., Zeidler, Th., Wang, Q., Morawe, Ch., Metoki, N., Zabel, H.: J. Appl. Phys. 77, 1055 (1995)
Houdy, P., Boher, P., Giron, F., Pierre, F.: J. Appl. Phys. 69, 5667 (1991)
Dekoster, J., Jedryka, E., Mény, C., Langouche, G.: Europhys. Lett. 22, 69 (1993); J. Magn. Magn. Mater. 121, 69 (1993)
Jay, J.Ph., Jedryka, E., Wójcik, M., Dekoster, J., Langouche, G., Panissod, P.: Z. Phys. B 101, 329 (1996)
Jay, J.Ph., Wójcik, M., Panissod, P.: Z. Phys. B 101, 421 (1996)
Finel, A, Ducastelle, F.: in: Phase transformations in solids. Materials Research Society Symposia Proc., vol. 21, p. 293. Amsterdam: North Holland 1987 Finel, A.: Thesis. University of Pierre and Marie Curie Paris 1987
Ducastelle, F.: Order and phase stability in alloys. Amsterdam, Oxford, New York: North Holland 1991
Elliot, R.P.: Constitution of binary alloys, [Suppl. 1], New York: Mac Graw Hill 1965; Shunk, F.A.: Constitution of binary alloys, [Suppl. 2], New York: Mac Graw Hill 1969
Treglia, G., Legrand, B.: Phys. Rev. B 35, 4338 (1987)
Maret, M, Cadeville, M.C., Staiger, W., Beaurepaire, E., Poinsot, R., Herr, A.: Thin Solid Films 275, 224 (1996)
Flynn, C. P.: Phys. Rev. Lett. 57, 599 (1986)
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Wojcik, M., Jay, J., Panissod, P. et al. New phases and chemical short range order in co-deposited CoFe thin films with bcc structure: an NMR study. Z. Phys. B - Condensed Matter 103, 5–12 (1997). https://doi.org/10.1007/s002570050327
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DOI: https://doi.org/10.1007/s002570050327