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Phonon Dispersion and Kohn Anomaues in the Alloy Cu0.84Al0.16

Published online by Cambridge University Press:  21 February 2011

Henry Chou
Affiliation:
Physics Department, Brookhaven National Laboratory, Upton, N.Y. 11973
S. M. Shapiro
Affiliation:
Physics Department, Brookhaven National Laboratory, Upton, N.Y. 11973
S. C. Moss
Affiliation:
Physics Department, University of Houston, Houston, Texas 77204-5504
Mark Mostoller
Affiliation:
Solid State Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831
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Abstract

We have made detailed measurements of phonon frequencies along all high-symmetry directions on a large single crystal of Cu0.84Al0.16 at room temperature. Phonon frequencies were ascertained to better than ±0.03 meV. Inter-atomic force constants and vibrational density of states were calculated by performing a Born-von Karman analysis on the complete set of phonon dispersion curves. In contrast to the case of pure Cu, no evident Kohn anomaly (neither in the phonon dispersion itself nor in the derivatives) was observed near the expected wave vector q=2kF. The absence of Kohn anomalies in the present system could be due either to a smeared out Fermi surface or to the possibility that the electron-electron interaction which screens the inter-ionic potential is not the dominant interaction in the system; i.e. the existence of Kohn anomalies in these alloys may depend mainly on the details of the electron-phonon interaction.

Type
Research Article
Copyright
Copyright © Materials Research Society 1990

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References

REFERENCES

1. Kohn, W., Phys. Rev. Lett. 2, 393 (1959)CrossRefGoogle Scholar
2. Brockhouse, B. N., Arase, T., Caglioti, G., Rao, K. R. and Woods, A. D. B., Phys. Rev. 128, 1099 (1962)CrossRefGoogle Scholar
3. Brockhouse, B. N., Arase, T., Caglioti, G., Sakamoto, M., Sinclair, R. N. and Woods, A. D. B. in Inelastic Scattering of Neutrons in Solids and Liquids, (International Atomic Energy Agency, Vienna, 1961)Google Scholar
4. Nilsson, G. and Rolandson, S., Phys. Rev. B9, 3278 (1974)CrossRefGoogle Scholar
5. Sharp, R. I., J. Phys. C2, 432 (1969)Google Scholar
6. Kittel, C. in Solid State Physics 22, 1 (1968) edited by H. Ehrenreich, D. Turnbull and F. Seitz (Academic Press, New York & London)Google Scholar
7. Varma, C. M. and Weber, W., Phys. Rev. Lett. 39, 1094 (1977)CrossRefGoogle Scholar
8. Krivoglaz, M. A., Theory of X-Ray and Thermal Neutron Scattering by Real Crystals, Plenum Press, New York, 1969 Google Scholar
9. Moss, S. C., Phys. Rev. Lett. 22, 1108 (1969)CrossRefGoogle Scholar
10. Scatttergood, R. O., Moss, S. C. and Bever, M. B., Acta Metal. 18, 1087 (1970)CrossRefGoogle Scholar
11. Pinski, F., private communicationGoogle Scholar
12. Cohen, J. B. and Hilliard, J. E., Local Atomic Arrangements Studied by X-Ray Diffraction (Gordon and Breach, 1962)Google Scholar
13. Buhrer, W., Reinhard, L., Schonfeld, B. and Kostorz, G., preprint, 1989 Google Scholar
14. Borle, B. and Sparks, C. J. Jr., Acta Cryst. 17, 827 (1964)Google Scholar
15. Landoldt-Bornstein, NS III/13a, p. 44 Google Scholar
16. Birgeneau, R. J., Cordes, J., Dolling, G. and Woods, A. D. B., Phys. Rev. 136, 1356 (1964)CrossRefGoogle Scholar
17. Nicklow, R. M., Vijayaraghavan, P. R., Smith, H. G., and Wilkinson, M. K., Phys. Rev. Lett. 20, 1245 (1968)CrossRefGoogle Scholar
18. Kaplan, T. and Mostoller, M., Phys. Rev. B9, 353 (1974)CrossRefGoogle Scholar
19. Nicklow, R. M., Gilat, G., Smith, H. G., Raubenheimer, L. J., and Wilkinson, M. K., Phys. Rev. 164, 922 (1967)CrossRefGoogle Scholar
20. Segall, B., Phys. Rev. 125, 109 (1962)CrossRefGoogle Scholar
21. Gyorffy, B. L. and Stocks, G. M., Phys. Rev. Lett. 50, 374 (1983)CrossRefGoogle Scholar