Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-27T16:55:13.294Z Has data issue: false hasContentIssue false
  • English
  • Français

Polarization effects in AlxGa1−xN / GaN superlattices

Published online by Cambridge University Press:  17 March 2011

Erik L. Waldron ,
E. Fred Schubert ,
John W. Graff ,
Andrei Osinsky ,
Michael J. Murphy  and
William F. Schaff
Erik L. Waldron
Affiliation:
Photonics Center, Boston University, Boston, Massachusetts 02215, U.S.A.
E. Fred Schubert
Affiliation:
Photonics Center, Boston University, Boston, Massachusetts 02215, U.S.A.
John W. Graff
Affiliation:
Photonics Center, Boston University, Boston, Massachusetts 02215, U.S.A.
Andrei Osinsky
Affiliation:
Corning Applied Technologies, Woburn, Massachusetts 01801, U.S.A.
Michael J. Murphy
Affiliation:
School of Electrical Engineering, Cornell University, Ithaca, New York 14853, U.S.A.
William F. Schaff
Affiliation:
School of Electrical Engineering, Cornell University, Ithaca, New York 14853, U.S.A.
Get access

Abstract

Room temperature and low temperature photoluminescence studies of AlxGa1−xN/GaN superlattices reveal a red shift of the dominant transition band relative to the bulk GaN bandgap. The shift is attributed to the quantum-confined Stark effect resulting from polarization fields in the superlattices. A theoretical model for the band-to-band transition energies based on perturbation theory and a variational approach is developed. Comparison of the experimental data with this model yields a polarization field of 4.6 × 105 V/cm for room temperature Al0.1Ga0.9N/GaN and 4.5 × 105 V/cm for room temperature Al0.2Ga0.8N/GaN. At low temperatures the model yields 5.3 × 105 V/cm for Al0.1Ga0.9N/GaN and 6.3 × 105 V/cm for Al0.2Ga0.8N/GaN. The emission bands exhibit a blue shift at high excitation densities indicating screening of internal polarization fields by photo-generated free carriers.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 639: Symposium G – GaN and Related Alloys-2000 , 2000 , G11.1
Copyright
Copyright © Materials Research Society 2001

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Schubert, E. F., Grieshaber, W., and Goepfert, I. D., Appl. Phys. Lett. 69, 3737 (1996).Google Scholar
2. Hsu, L. and Walukiewicz, W., Appl. Phys. Lett. 74, 2405 (1999).Google Scholar
3. Goepfert, I. D., Schubert, E. F., Osinsky, A., and Norris, P. E., Electron. Lett. 35, 1109 (1999).Google Scholar
4. Kozodoy, P., Smorchkova, Y. P., Hansen, M., Xing, Huili, DenBaars, S. P., Mishra, U. K., Saxler, A. W., Perrin, R., and Mitchel, W. C., Appl. Phys. Lett. 75, 2444 (1999). See also P. Kozodoy, M. Hansen, S. P. DenBaars, and U. K. Mishra, Appl. Phys. Lett. 74, 3681 (1999).Google Scholar
5. Saxler, A., Mitchel, W. C., Kung, P., and Razeghi, M., Appl. Phys. Lett. 74, 2023 (1999).Google Scholar
6. Fiorentini, V., Bernardini, F., Sala, F. Della, Carlo, A. Di, and Lugli, P., available at http://xxx.lanl.gov/abs/condmat/9808098. See also F. Bernardini, V. Fiorentini, Phys. Rev. B 57, R9427 (1998). See also F. Bernardini, V. Fiorentini, and D. Vanderbilt, Phys. Rev. Lett. 79, 3958 (1997). See also F. Bernardini, V. Fiorentini, and D. Vanderbilt, Phys. Rev. B 56, R10 024 (1997).Google Scholar
7. Ambacher, O., Smart, J., Shealy, J. R., Weimann, N. G., Chu, K., Murphy, M., Schaff, W. J., Eastman, L. F., Dimitrov, R., Wittmer, L., Stutzmann, M., Rieger, W., and Hilsenbeck, J., J. Appl. Phys. 85, 3222 (1999).Google Scholar
8. Sala, Fabio Della, Carlo, Aldo Di, Lugli, Paolo, Bernardini, Fabio, Fiorentini, Vincenzo, Scholz, Reinhard, and Jancu, Jean-Marc, Appl. Phys. Lett. 74, 2002 (1999).Google Scholar
9. Grandjean, N., Damilano, B., Dalmasso, S., Leroux, M., Laügt, M., and Massies, J., J. Appl. Phys. 86, 3714 (1999).Google Scholar
10. Yu, E. T., Dang, X. Z., Yu, L. S., Qiao, D., Asbeck, P. M., Lau, S. S., Sullivan, G. J., Boutros, K. S. and Redwing, J. M., Appl. Phys. Lett 73, 1880 (1998).Google Scholar
11. Leroux, M., Grandjean, N., Laügt, M., Massies, J., Gil, B., Lefebvre, P., and Bigenwald, P., Phys. Rev. B 58, R13 371 (1998).Google Scholar
12. Kim, H. S., Lin, J. Y., Jiang, H. X., Chow, W. W., Botchkarev, A., and Morkoç, H., Appl. Phys. Lett. 73, 3426 (1998).Google Scholar
13. Lefebvre, P., Gil, B., Allègre, J., Mathieu, H., Grandjean, N., Leroux, M., Massies, J., and Bigenwald, P., MRS Internet J. Nitride Semicond. Res. 4S1, G3.69 (1999).Google Scholar
14. Grandjean, N., Massies, J., and Leroux, M., Appl. Phys. Lett. 74, 2361 (1999).Google Scholar
15. Simon, J., Langer, R., Barski, A., and Pelekanos, N. T., Phys. Rev. B 61, 7211 (2000).Google Scholar
16. Im, Jin Seo, Kollmer, H., Off, J., Sohmer, A., Scholz, F., and Hangleiter, A., Phys. Rev. B 57, R9435 (1998).Google Scholar
17.It is well known that the oscillator strength is reduced due to piezoelectric effects in AlxGa1−xN / GaN quantum wells. Because the oscillator strengths do not affect the main photon transition energies, we do not consider them.Google Scholar