Biomedical Engineering Reference
In-Depth Information
up of two
non-identical
QDs. Our study revealed that the built-in field in a QDM
can be effectively reduced compared to a single QD, leading to a further increase
in the spatial overlap of electron and hole wave functions. These results are in
qualitative agreement with experimental data [
21
,
22
] for stacked nitride QDs, where
PL measurements show reduced recombination lifetimes, indicative of an increased
spatial overlap of electron and hole wave functions. Furthermore, due to the behavior
of the built-in field in a system of stacked QDs, the distance between the two QDs
can be used to engineer the optical recombination rate. Overall, we conclude that
stacked nitride QDs therefore have significant potential for use in high efficiency
light emitters with high indium content, of strong benefit for future optoelectronic
devices and their applications.
Acknowledgments
The authors acknowledge the financial support from Science Foundation
Ireland. S. Schulz was further supported by the Irish Research Council for Science, Engineering
and Technology (IRCSET).
References
1. Jarjour, A.F., Oliver, R.A., Taylor, R.A.: Phys. Status Solid A
206
, 2510 (2009)
2. Humphreys, C.J.: MRS Bull.
33
, 459 (2008)
3. Nakamura, S., Mukai, T., Senoh, M.: Appl. Phys. Lett.
64
, 1687 (1994)
4. Nakamura, S.: J. Sel. Top. Quant. Electron.
3
, 712 (1997)
5. Yang, W., Lee, H., Johnson, T.J., Sercel, P.C., Norman, A.G.: Phys. Rev. B
61
, 2784 (2000)
6. Simon, J., Pelekanos, N.T., Adelmann, C., Martinez-Guerrero, E., Andre, R., Daudin, B., Dang,
L.S., Mariette, H.: Phys. Rev. B
68
, 035312 (2003)
7. Andreev, A.D., O'Reilly, E.P.: Phys. Rev. B
62
, 15851 (2000)
8. Schulz, S., Caro, M.A., O'Reilly, E.P., Marquardt, O.: Phys. Status Solid B
249
, 521 (2012)
9. Waltereit, P., Brandt, O., Trampert, A., Grahn, H.T., Menniger, J., Ramsteiner, M., Ploog,
K.H.: Nature
406
, 865 (2000)
10. Founta, S., Rol, F., Bellet-Amalric, E., Bleuse, J., Daudin, B., Gayral, B., Mariette, H., Mois-
son, C.: Appl. Phys. Lett.
86
, 171901 (2005)
11. Schulz, S., Caro, M.A., O'Reilly, E.P.: Appl. Phys. Lett.
101
, 113107 (2012)
12. Kim, K.C., Schmidt, M.C., Sato, H., Wu, F., Fellows, N., Saito, M., Fujito, K., Speck,
J.S., Nakamura, S., DenBaars, S.P.: Phys. Stat. Sol. (RRL)
1
, 125 (2007)
13. Caro, M.A., Schulz, S., Healy, S.B., O'Reilly, E.P.: J. Appl. Phys.
109
, 084110 (2011)
14. Zhang, M., Banerjee, A., Lee, C.S., Hinckley, J.M., Bhattacharya, P.: Appl. Phys. Lett.
98
,
221104 (2011)
15. Wu, Y.R., Lin, Y.Y., Huang, H.H., Singh, J.: J. Appl. Phys.
105
, 013117 (2009)
16. Schulz, S., O'Reilly, E.P.: Phys. Rev. B
82
, 033411 (2010)
17. Zhang, M., Bhattacharya, P., Guo, W.: Appl. Phys. Lett.
97
, 011103 (2010)
18. Soh, C.B., Liu, W., Chua, S.J., Ang, S.S., Tan, R.J.N., Chow, S.Y.: J. Appl. Phys.
108
, 093501
(2010)
19. Schmidt, O.G., Kirstaedter, N., Ledentsov, N.N., Mao, M.H., Bimberg, D., Ustinov,
V.M., Egorov, A.Y., Zhukov, A.E., Maximov, M., Kop'ev, P.S., Alferov, Z.I.: Electron. Lett.
32
, 1302 (1996)
20. Ledentsov, N.N., Shchukin, V.A., Grundmann, M., Kirstaedter, K., Bohrer, J., Schmidt, O.,
Bimberg, D., Ustinov, V.M., Egorov, A.Y., Zhukov, A.E., Kop'ev, P.S., Zaitsev, S.V., Gordeev,
N.Y., Alferov, Z.I., Borovkov, A.I., Kosogov, A.O., Ruvimov, S.S., Werner, P., Gosele,
U., Heydenreich, J.: Phys. Rev. B
54
, 8743 (1996)
