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InP under high pressures

Published online by Cambridge University Press:  31 January 2011

M-H. Tsai ,
John D. Dow  and
R.V. Kasowski
M-H. Tsai
Affiliation:
Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287
John D. Dow
Affiliation:
Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287
R.V. Kasowski
Affiliation:
E. I. du Pont de Nemours and Company, Central Research and Development Department, Experimental Station, Wilmington, Delaware 19880-0328
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Abstract

The direct energy gaps, Eg, and the indirect gaps at the X point, E(X), of GaAs and AlxGa1−xAs alloys are essentially linear functions of hydrostatic pressure, P. Recent photoluminescence measurements of Tozer et al. for InP under high pressures, however, found that Eg(P) is not quite linear, but bends down slightly at high pressures. Using the first-principles pseudofunction method, we have calculated Eg and E(X) as functions of pressure, as well as the zero-temperature equation of state P(V). Our calculated gap curve for InP, Eg(P), bends down slightly, as found in photoluminescence studies. The slope dEg/dP is 8.8 meV/kbar for small pressures P, and is in good agreement with the experimental value, 8.32 meV/kbar. The observed nonlinearity in the dependence of Eg on pressure for InP is attributed to a large derivative of the bulk modulus with respect to pressure. The calculated bond length, bulk modulus, and critical pressure for a phase transition from the zinc blende to a rocksalt structure, and the unit cell volume change at this phase transition are all in good agreement with the data.

Type
Articles
Information
Journal of Materials Research , Volume 7 , Issue 8 , August 1992 , pp. 2205 - 2210
Copyright
Copyright © Materials Research Society 1992

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References

1.Wolford, D. J. and Bradley, J. A., Solid State Commun. 53, 1069 (1985).CrossRefGoogle Scholar
2.Wolford, D. J., Kuech, T. F., Steiner, T. W., Bradley, J. A., Gell, M. A., Ninno, D., and Jaros, M., Superlatt. Microstmct. 4, 525 (1988) and references therein.CrossRefGoogle Scholar
3.Tozer, S. W., Wolford, D. J., Bradley, J. A., Bour, D., and Stringfellow, G. B., International Conference on the Physics of Semiconductors, edited by Zawadzki, W. (Warsaw, Poland, Institute of Physics, Polish Academy of Sciences, 1988), Vol. 2, p. 881. These data were taken at room temperature, but thermal shifts of band edges in semiconductors are known to be sufficiently small, typically 10−3 eV/K (Ref. 4), that comparison with lowtemperature theory is appropriate here. For example, E(X) at room temperature is 2.04 eV in InP.Google Scholar
4.Landolt—Börnstein, R., Numerical Data and Functional Relationships in Science and Technology, Vol. 17a in Crystal and Solid State Physics (Springer, Berlin, 1984).Google Scholar
5.Vogl, P., Hjalmarson, H. P., and Dow, J. D., J. Phys. Chem. Solid 44, 365 (1983).CrossRefGoogle Scholar
6.Kohn, W. and Sham, L. J., Phys. Rev. 140, 1133 (1965); P. Hohenberg and W. Kohn, Phys. Rev. 136, B864 (1964).CrossRefGoogle Scholar
7.Hybertsen, M. S. and Louie, S. G., Phys. Lett. 55, 1418 (1985).CrossRefGoogle Scholar
8.Hedin, L. and Lundqvist, B. I., J. Phys. C4, 2064 (1971). (1985).Google Scholar
9.Kasowski, R. V., Tsai, M-H., Rhodin, T. N., and Chambliss, D. D., Phys. Rev. B 34, 2656 (1986).CrossRefGoogle Scholar
10.Tsai, M-H., Dow, J. D., and Kasowski, R. V., Phys. Rev. B 38, 2176 (1988).CrossRefGoogle Scholar
11.Tsai, M-H., Dow, J. D., Newman, K. E., and Kasowski, R. V., Phys. Rev. B 41, 7744 (1990).CrossRefGoogle Scholar
12. Since the bond length in the rocksalt structure is larger than that in the zinc-blende structure, we used a larger muffin-tin radius for P in the former structure. This is necessary in order to compare total energies between the two different structures on the same footing. The muffin-tin radii for In were 2.50 as, where a% is the hydrogenic Bohr radius; for P, the muffin-tin radii were chosen to be 1.80 QB for the zinc-blende structure and 2.20 a% f°r rocksalt, to reflect the larger In-P bond length.Google Scholar
13.Chadi, D. J. and Cohen, M. L., Phys. Rev. B 8, 5747 (1973).CrossRefGoogle Scholar
14.Murnaghan, F. D., Proc. Natl. Acad. Sci. U.S.A. 30, 244 (1944); M. T. Yin and M. L. Cohen, Phys. Rev. B 26, 5668 (1982).CrossRefGoogle Scholar
15.Zhang, S. B. and Cohen, M. L., Phys. Rev. B 35, 7604 (1987).CrossRefGoogle Scholar
16.CRC Handbook of Chemistry and Physics, 66th ed., edited by Weast, R. C., Astle, M. J., and Beyer, W. H. (1985–1986).Google Scholar
17. Since thermal expansion and pressure corrections for the lattice constants have opposite signs, the difference between zeropressure, zero-temperature and one-atmosphere, room-temperature lattice constants is commonly small: for example, in bulk Si the zero-temperature, zero-pressure bond length is 2.3508 Å, compared with 2.3516 Å at room temperature and one atmosphere pressure.Google Scholar
18. This value is estimated from data for Ini-xGaxP alloys given in Ref. 3.Google Scholar
19.Pitt, G. D., Solid State Commun. 8, 1119 (1970); J. Phys. C 6, 1586 (1973).CrossRefGoogle Scholar
20.Kobayashi, T., Tei, T., Aoki, K., Yamamoto, K., and Abe, K., J. Lumin. 24/25, 347 (1981).CrossRefGoogle Scholar
21.Kobayashi, T., Aoki, K., and Yamamoto, K., Physica 139 & 140B, 537 (1986).Google Scholar
22.Harrison, W. A., Electronic Structure and the Properties of Solids (Freeman, San Francisco, 1980).Google Scholar