Hostname: page-component-8448b6f56d-c47g7 Total loading time: 0 Render date: 2024-04-18T22:57:12.105Z Has data issue: false hasContentIssue false

Phonon Overheating in Quantum Dots: Low Electronic Densities

Published online by Cambridge University Press:  01 February 2011

Karel Král*
Affiliation:
kral@fzu.cz, Institute of Physics, Academy of Sciences of Czech Republic, Dept. of Cond. Matter Theory, Na Slovance 2, Prague 8, 188221, Czech Republic, +420266052772, +420286890527
Get access

Abstract

The electronic coupling to the longitudinal optical phonons has been recently used to interpret theoretically the electronic energy relaxation in quantum dots. In this theory the LO phonon modes served as a reservoir, on which the electron executes multiple scattering acts. Quite reasonably such a phonon subsystem is expected to be passive, namely, in a long-time limit of development, the whole system should be able to achieve such a stationary state, in which the statistical distributions of both subsystems, electron and phonons, do not change in time. We remind briefly that the recent approach to the relaxation in quantum dots has led to a non-passivity of such a reservoir. We remind as well the method of a partial elimination of the phonon overheating effect by using the Lang-Firsov transformation. Then we apply such a modified relaxation theory to the electronic relaxation at low electronic densities in quantum dots and come to conclusions concerning the role of e-LO scattering mechanism. We show that the modified theory of relaxation gives a plausible dependence of relaxation rate on temperature of sample. We also come to conclusions that at low levels of electronic excitation of quantum dot sample the electron-LO phonon mechanism can become relatively weak with respect to other relaxation mechanisms not supporting the electronic up-conversion effect.

Type
Research Article
Copyright
Copyright © Materials Research Society 2007

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. Bhattacharya, P., Kamath, K. K., Singh, J., Klotzkin, D., Phillips, J., Jiang, H.-T., Chervela, N., Norris, T. B., Sosnowski, T., Laskar, J., Murty, M. R., “In(Ga)As/GaAs selforganized quantum dot lasers: DC and small-signal modulation properties”, IEEE Trans. on Electron Devices 46, 871883 (1999).Google Scholar
2. Markus, A., Chen, J. X., Paranthoen, C., Fiore, A., Platz, C., Gautier-Lafaye, O., “Simultaneous two-state lasing in quantum-dot lasers”, Appl. Phys. Lett. 82, 18181820 (2003).Google Scholar
3. Viktorov, E. A., Mandel, P., Tanguy, Y., Houlihan, J., Huyet, G.: Electron-hole asymmetry and two-state lasing in quantum dot lasers, Appl. Phys. Lett. 87, 053113 (2005).Google Scholar
4. Král, K., Zdeněk, P., Khás, Z.: Transient processes and luminescence upconversion in zerodimensional nanostructures, Surf. Sci., 566–568, 321326 (2004); K. Král, P. Zdeněk, Z. Khás: Electronic transient processes and optical spectra in quantum dots for quantum computing, IEEE Trans. on Nanotechnology, 3, 17–25 (2004).Google Scholar
5. Velický, B., Kalvová, A., Špička, V., Journal of Physics: Conference Series 35, 116 (2006).Google Scholar
6. Tsuchiya, H., Miyoshi, T., J. Appl. Phys. 83, 25742585 (1998); K. Král, Z. Khás, phys. stat. sol. (b) 208, R5-R6; K. Král, Z. Khás, arXiv:cond-mat/0103061.Google Scholar
7. Král, K., Czechoslovak J. Phys., 56, 3340 (2006).Google Scholar
8. Zhang, L., Boggess, T. F., Gundogdu, K., Flatté, M. E., Deppe, D. G., Cao, C., Shchekin, O. B., Appl. Phys. Lett., 79, 33203322 (2001); E. U. Rafailov, Appl. Phys. Lett., 88, 041101 (2006).Google Scholar
9. Inoshita, T. and Sakaki, H., Phys. Rev. Lett 46, 7260 (1992).Google Scholar