Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-08T07:17:44.475Z Has data issue: false hasContentIssue false

Photoexcitation Dynamics In Polymeric Heterostructures

Published online by Cambridge University Press:  10 February 2011

G. Bongiovanni
Affiliation:
Dipartimento di Scienze Fisiche, UniversitA di Cagliari, Cagliari, 09124 Italy.
S. Destri
Affiliation:
Istituto di Chimica delle Macromolecole-C.N.R., Via Bassini 15, Milano, 20133 Italy.
A. Mura
Affiliation:
Dipartimento di Scienze Fisiche, UniversitA di Cagliari, Cagliari, 09124 Italy.
A. Piaggi
Affiliation:
Istituto di Matematica e Fisica, UniversitA di Sassari, Sassari, 07100 Italy.
R Tubino
Affiliation:
Dipartimento di Fisica, UniversitA di Milano, Milano, 20133 Italy
Get access

Abstract

We investigate the dynamics of photoexcitations in thiophene-based copolymers by site-selective and time-resolved photoluminescence spectroscopies. We attribute the large Stokes-shift observed between the absorption and luminescence peaks to spectral relaxation of excitons within an inhomogeneously broadened density of states. The non exponential decay of the photoluminescence intensity is explained through the interplay between spectral diffusion, thermally activated jumps and slow transfer to non nearest neighbour sites.

Type
Research Article
Copyright
Copyright © Materials Research Society 1996

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. Kanner, G.S., Wei, X., Hess, B.C., Chen, L.R., and Vardeny, Z.V., Phys. Rev. Lett. 69, 538 (1992), and references therein;T.A., Skotheim, Handbook of Conducting Polymers, M. Dekker, New York, 1986; S.Etemad and Z.G. Soos, in Spectroscopy of advanced Materials, edited by R.J.H. Clark and R.E. Hester (Wiley, New York, 1991);.Google Scholar
2. Kersting, R., Lemmer, U., Mahrt, R.F., Leo, K., Kurz, H., Bdissler, H., and Göbel, E.O., Phys. Rev. Lett. 70, 3820 (1993); U. Lemmer, R.F. Mahrt, Y.Wada, A. Greiner, H. Bdssler, and E.O. Göbel, Chem. Phys. Lett. 209, 243 (1993).Google Scholar
3. Yan, M., Rothberg, L.J., Papadimitrakopoulos, F., Galvin, M.E., and Miller, T.M., Phys. Rev. Lett. 73, 744 (1994); M. Yan, L.J. Rothberg, E.W. Kwock, and T.M. Miller, Phys. Rev. Lett. 75, 1992 (1995).Google Scholar
4. Kersting, R., Lemmer, U., Deussen, M., Bakker, H.J., Mahrt, R.F., Kurz, H., Arkhipov, V.I., Bdissler, H., and Göbel, E.O, Phys. Rev. Lett. 73, 1440 (1994).Google Scholar
5. Lemmer, U., Mahrt, R.F., Wada, Y., Greiner, A., Bässler, H., and Göbel, E.O., Appl. Phys. Lett. 62, 2827 (1993).Google Scholar
6. Mukamel, S. and Wang, H.X., Phys. Rev. Lett. 69, 65 (1992).Google Scholar
7. Meyers, F., Heeger, A.J., and Brédas, J.L., J. Chem. Phys. 97, 2750 (1992); T. Yoshimura, Optics Commun. 70, 535 (1989); A. Piaggi, R.Tubino, and L.Colombo, Phys. Rev. B 51 1624 (1995).Google Scholar
8. Botta, C., Destri, S., Porzio, W., and Tubino, R., J. Chem. Phys. 102, 1836 (1994).Google Scholar
9. Kanemitsu, Y., Suzuki, K., Masumoto, Y., Tomiuchi, Y., Shiraishi, Y., and Kuroda, M., Phys. Rev. B 50, 2301 (1994).Google Scholar
10. Rauscher, U., Bässler, H., Bradley, D.D.C., and Hennecke, M., Phys. Rev. B 42, 9830 (1990).Google Scholar
11. Pautmeier, L., Rauscher, U., and Bässler, H., J. Chem. Physics 146, 291 (1990); R.F. Mahrt and H. Bdssler, Synth. Metals 45, 107 (1991).Google Scholar
12. Dippel, O., Brandl, V., Bässler, H., Danieli, R., Zamboni, R., and Taliani, C., Chem. Phys. Lett. 216, 418 (1993).Google Scholar
13. Möller, K.D. and Bothschild, W.G., Far Infrared Spectroscopy, Wiley, New York, 1971.Google Scholar
14. Chosrovian, H., Rentsch, S., Grehner, D., Dahm, D.U., and Birckner, E., Synth. Metals 60, 23 (1993).Google Scholar
15. Powell, R. and Soos, Z.G., Journal of Luminescence 11, 45 (1975).Google Scholar
16. Fractals in Science, edited by Bunde, A. and Havlin, S. (Springer-Velag, Berlin, 1994), p. 119- 159.Google Scholar
17. Blumen, A., Klafter, J., White, B.S., and Zumofen, G., Phys. Rev. Lett. 53, 1301 (1984); H. Sher, M.F. Shlesinger, and J.T. Bendler, Physcs Today 1, 26 (1991).Google Scholar
18. Dexheimer, S.L., Vareka, W.A., Mittleman, D., Zettl, A., and Shank, C.V., Chem. Phys. Lett. 235, 552 (1995).Google Scholar
19. Solubility of (T3B2)n is indeed quite low. Thus, inter-chain jumps are only weakly prevented in solution, contributing to the fast non exponential decay at short delay times.Google Scholar