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Quantum-Confined Electron Transitions in CdSe Nanocrystals

Published online by Cambridge University Press:  17 March 2011

D. S. Ginger
Affiliation:
Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE, U.K.
A. S. Dhoot
Affiliation:
Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE, U.K.
C. E. Finlayson
Affiliation:
Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE, U.K.
N. C. Greenham
Affiliation:
Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE, U.K.
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Abstract

We present quasi-steady-state photoinduced absorption measurements on thin films of colloidal CdSe nanocrystals. We observe an intense, size-dependent absorption peaking in the mid-infrared when the samples are irradiated with visible light. The absorption is accompanied by a bleach in the visible near the position of the first excitonic absorption and persists with a lifetime of milliseconds at room temperature. We characterize the lifetime of the electron state and its cross-section. We attribute this feature to the 1S-1P transition of a delocalized electron. We report a bleaching of the first excitonic transition in electrically excited nanocrystal-based diode structures, and attribute it to charging of the 1S electron state.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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References

REFERENCES

1 Murray, C. B., Norris, D. J., and Bawendi, M. G., J. Am. Chem. Soc. 15, 87068715 (1993).Google Scholar
2 Katari, J. E. Bowen, Colvin, V. L., and Alivisatos, A. P., J. Phys. Chem. 98, 41094117 (1994).Google Scholar
3 Peng, X., Wickham, J., and Alivisatos, A. P., J. Am. Chem. Soc. 120, 53435344 (1998).Google Scholar
4 Bruchez, M. Jr., Moronne, M., Gin, P., Weiss, S., and Alivisatos, A. P., Science 281, 20132015 (1998).Google Scholar
5 Chan, W. C. W. and Nie, S., Science 281, 2016 (1998).Google Scholar
6 Colvin, V. L., Schlamp, M. C., and Alivisatos, A. P., Nature 370, 354357 (1994).Google Scholar
7 Greenham, N. C., Peng, X., and Alivisatos, A. P., Phys. Rev. B 54, 1762817637 (1996).Google Scholar
8 Klimov, V. I., Mikhailovsky, A. A., McBranch, D. W., Leatherdale, C. A., and Bawend, M. G.i, Science 287, 10111013 (2000).Google Scholar
9 Guyot-Sionnest, P., Shim, M., Matranga, C., and Hines, M., Phys. Rev. B 60, R2181–R2184 (1999).Google Scholar
10 Klimov, V. I., McBranch, D. W., Leatherdale, C. A., and Bawendi, M. G., Phys. Rev. B. 60, 1374013749 (1999).Google Scholar
11 Klimov, V. I., Schwarz, C. J., McBranch, D. W., Leatherdale, C. A., and Bawendi, M. G., Phys. Rev. B. 60, R2177–R2180 (1999).Google Scholar
12 Guyot-Sionnest, P. and Hines, M. A., Appl. Phys. Lett. 72, 686 (1998).Google Scholar
13 Brus, L. and Nirmal, M., Acc. Chem. Res. 32, 407414 (1999).Google Scholar
14 Efros, A. L. and Rosen, M., Phys. Rev. Lett. 78, 1110 (1997).Google Scholar
15 Kuno, M., Fromm, D. P., Hamann, H. F., Gallagher, A., and Nesbitt, D. J., J. Chem. Phys. 112, 31173120 (2000).Google Scholar
16 Ginger, D. S. and Greenham, N. C., Phys. Rev. B 59, 1062210629 (1999).Google Scholar
17 Ginger, D. S. and Greenham, N. C., J. Appl. Phys. 87, 13611368 (2000).Google Scholar
18 Krauss, T. D. and Brus, L. E., Phys. Rev. Lett. 83, 48404843 (1999).Google Scholar
19 Shim, M., Shilov, S. V., Braiman, M. S., and Guyot-Sionnest, P., J. Phys. Chem. B 104, 14941496 (2000).Google Scholar
20 Ginger, D. S., Dhoot, A. S., Finlayson, C. E., and Greenham, N. C., Appl. Phys. Lett. 77, 28162818 (2000).Google Scholar
21 Shim, M. and Guyot-Sionnest, P., Nature 407, 981983 (2000).Google Scholar
22 Kuno, M., Lee, J. K., Dabousi, B. O., Mikulec, F. V., and Bawendi, M. G., J. Chem. Phys. 106, 98699882 (1997).Google Scholar
23 Ginger, D. S. and Greenham, N. C., Mat. Res. Soc. Symp. Proc. 571, 185190 (2000).Google Scholar
24 Kagan, C. R., Murray, C. B., Nirmal, M., and Bawendi, M. G., Phys. Rev. Lett. 76, 15171520 (1996).Google Scholar
25 Efros, A. L. and Rosen, M., Annu. Rev. Mater. Sci. 30, 475521 (2000).Google Scholar
26 Norris, D. J. and Bawendi, M. G., Phys. Rev. B 53, 1633816346 (1996).Google Scholar
27 Sacra, A., Norris, D. J., Murray, C. B., and Bawendi, M. G., J. Chem. Phys. 103, 52365245 (1995).Google Scholar