Hostname: page-component-8448b6f56d-sxzjt Total loading time: 0 Render date: 2024-04-25T03:45:41.844Z Has data issue: false hasContentIssue false
  • English
  • Français

Electric Field Induced Ionization of the Exciton in Poly(Phenylene Vinylene)

Published online by Cambridge University Press:  21 March 2011

Jian Wang ,
Daniel Moses ,
Alan J. Heeger ,
N. Kirova  and
S. Brazovski
Jian Wang
Affiliation:
Institute for Polymers and Organic Solids, University of California, Santa Barbara, CA 93103, U.S.A.
Daniel Moses
Affiliation:
Institute for Polymers and Organic Solids, University of California, Santa Barbara, CA 93103, U.S.A.
Alan J. Heeger
Affiliation:
Institute for Polymers and Organic Solids, University of California, Santa Barbara, CA 93103, U.S.A.
N. Kirova
Affiliation:
LPTMS, Bat.100, Universite Paris-Sud, 91405, Orsay-Cedex, France
S. Brazovski
Affiliation:
LPTMS, Bat.100, Universite Paris-Sud, 91405, Orsay-Cedex, France
Get access

Abstract

The exciton binding energy (Eb) and the band gap energy (Eg) of poly(phenylene vinylene), PPV, have been determined by photoconductivity excitation profile spectroscopy as a function of light polarization, applied electric field, and temperature. The spectral signature of the exciton is a narrow peak (100 meV full width at half maximum) that emerges just below the band edge upon increasing the external field, the temperature or the defect density. The exciton peak is observed only for light polarized parallel to the chain axis. The exciton binding energy is obtained from the energy of the exciton peak with respect to the band edge and, independently from analysis of the field dependence of the exciton dissociation. It is Eb ≈ 60 meV.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 660: Symposia JJ – Organic Electronic & Photonic Materials and Devices , 2000 , JJ2.10
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. Heeger, A. J., Nature of the primary photo-excitations in poly(arylene-vinylenes): bound neutral excitons or charged polaron pairs, The Nature of Photoexcitations in Conjugated Polymers, ed. Sariciftci, N. S. (World Scientific Publ., Singapore, 1997) pp. 20–50.Google Scholar
2. Pope, M. and Swenberg, C. E., Electronic Processes in Organic Crystals (Oxford University press, New York, 1982).Google Scholar
3 Enck, R. C. and Pfister, G., Chalcogenides, Amorphous, Photoconductivity and Related Phenomena, ed. Mort, J. and Pai, D. M. (Elsevier Scientific Publications, New York, 1976) pp. 215–302.Google Scholar
4. A recent theoretical extension of the Onsager solution has been developed by Scher, H. and Rackovsky, S., J. Chem. Phys. 81, 1994 (1984).Google Scholar
5. Harrison, M. G., Gruner, J., and Spencer, G.C.W., Phys. Rev. B 55, 7831 (1997).Google Scholar
6. Moses, D., Wang, J., Yu, G., Heeger, A.J., Phys. Rev. Lett. 80, 2685 (1998).Google Scholar
7. Moses, D. and Heeger, A.J., in Relaxation in Polymers, ed. Kobayashi, T. (World Scientific, Singapore, 1993).Google Scholar
8. Moses, D., Phys. Rev. B 53, 4462–70 (1996).Google Scholar
9. Arkhipov, V.I., Emelianova, E.V., and Bassler, H., Chem. Phys. Lett. 296, 452 (1998).Google Scholar
10. Moses, D., Dogariu, A., Heeger, A.J., Chem. Phys. Lett. 316 (5-6), 354 (2000).Google Scholar
11. Moses, D., Dogariu, A., Heeger, A.J., Phys. Rev. B 61(14), 9373 (2000).Google Scholar
12. Bredas, J. L., Cornil, J., Heeger, A.J., Adv. Mat. 8(5), 447 (1996).Google Scholar
13. Pakbaz, K., Lee, C.H., Heeger, A. J., Hagler, T. W., McBranch, D., Synth. Met. 64, 295 (1994).Google Scholar
14. Campbell, I. H., Hagler, T.W., Smith, D.L., Ferraris, J.P., Phys. Rev. Lett. 76(11), 1900 (1996).Google Scholar
15. Chandross, M., Mazumdar, S., Jeglinski, S., Wei, X., Vardeny, Z.V., Kwock, E.W., Miller, T.M., Phys. Rev. B 50(19), 14702 (1994).Google Scholar
16. Rohlfing, M., Louie, S., Phys. Rev. Lett. 82(9), 1959 (1999).Google Scholar
17. The first measurements of the photocurrent excitation spectra using polarized light were done by Lee, C.H., Park, J.Y., Moses, D., Heeger, A.J., Noguchi, T., Ohnishi, T., Synth. Met. 101(1-3), 444 (1999).Google Scholar
18. Comoretto, D., Dellepiane, G., Moses, D., Cornil, J., Santos, D.A., Bredas, J.L., Chem. Phys. Lett. 289, 1 (1998).Google Scholar
19. Hagler, T. W., Pakbaz, K., Voss, K.F., Heeger, A.J., Phys. Rev. B 44(16), 8652 (1991).Google Scholar
20. Increase of the photocurrent upon increasing defect concentration was observed by Antoniadis, H., Rothberg, L.J., Papadimitrakopoulos, F., Yan, M., Galvin, M.E., Abkowitz, M.A., Phys. Rev. B 50(20), 14911 (1994).Google Scholar
21. Kersting, R., Lemmer, U., Deussen, M., Bakker, H. J., Mahrt, R. F., Kurz, H., Arkhipov, V. I., Bässler, H., and Göbel, E. O., Phys. Rev. Lett. 73, 1440 (1994).Google Scholar
22. Kirova, N. and Brazovskii, S., to be published.Google Scholar
23. More details on these experimental results will be published in future publication.Google Scholar