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Photorefractive Conjugated Polymer-Liquid Crystal Composites

Published online by Cambridge University Press:  10 February 2011

M. R. Wasielewski ,
B. A. Yoon ,
M. Fuller ,
G. P. Wiederrecht ,
M. P. Niemczyk  and
W. A. Svec
M. R. Wasielewski
Affiliation:
Department of Chemistry, Northwestern University, Evanston, IL, 60208-3113
B. A. Yoon
Affiliation:
Department of Chemistry, Northwestern University, Evanston, IL, 60208-3113
M. Fuller
Affiliation:
Department of Chemistry, Northwestern University, Evanston, IL, 60208-3113
G. P. Wiederrecht
Affiliation:
Chemistry Division, Argonne National Laboratory, Argonne, IL, 60439-4831
M. P. Niemczyk
Affiliation:
Chemistry Division, Argonne National Laboratory, Argonne, IL, 60439-4831
W. A. Svec
Affiliation:
Chemistry Division, Argonne National Laboratory, Argonne, IL, 60439-4831
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Abstract

A new mechanism for space-charge field formation in photorefractive liquid crystal composites containing poly(2,5-bis(2′-ethylhexyloxy)-l,4-phenylenevinylene) (BEH-PPV) and the electron acceptor N,N′-dioctyl-1,4:5,8-naphthalenediimide, NI, is observed. Using asymmetric energy transfer (beam coupling) measurements that are diagnostic for the photorefractive effect, the direction of beam coupling as a function of grating fringe spacing inverts at a spacing of 5.5 μm. We show that the inversion is due to a change in the dominant mechanism for space-charge field formation. At small fringe spacings, the space-charge field is formed by ion diffusion in which the photogenerated anion is the more mobile species. At larger fringe spacings, the polarity of the space charge field inverts due to dominance of a charge transport mechanism in which photogenerated holes are the most mobile species due to hole migration along the BEH-PPV chains coupled with interchain hole hopping. Control experiments are presented, which use composites that can access only one of the two charge transport mechanisms. The results show that charge migration over long distances leading to enhanced photorefractive effects can be obtained using conjugated polymers dissolved in liquid crystals.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 597: Symposium PP – Thin Films for Optical Waveguide Devices & Materials … , 1999 , 211
Copyright
Copyright © Materials Research Society 2000

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References

1 Moerner, W. E., Silence, S. M., Hache, F., and Bjorklund, G. C., J Opt. Soc. Am. B 11, 320–30 (1994).Google Scholar
2 Meerholz, K., Volodin, B. L., Sandalphon, Kippelen, B., and Peyghambarian, N., Nature 371, 497–500 (1994).Google Scholar
3 A. Grunnet-Jepsen, Thompson, C. L., Twieg, R. J., and Moerner, W. E., Appl. Phys. Lett 70, 1515–1517 (1997).Google Scholar
4 Rudenko, E. V. and Sukhov, A. V., JETP Lett. 59, 142–46 (1994).Google Scholar
5 Khoo, I. C., Li, H., and Liang, Y., Opt. Lett. 19, 1723–25 (1994).Google Scholar
6 Wiederrecht, G. P., Yoon, B. A., and Wasielewski, M. R., Science 270, 1794–97 (1995).Google Scholar
7 Wiederrecht, G. P. and Wasielewski, M. R., J. Am. Chem. Soc. 120, 3231–3236 (1998).Google Scholar
8 Golemme, A., Volodin, B. L., Kippelen, B., and Peyghambarian, N., Opt. Lett. 22, 1226–28(1997).Google Scholar
9 Ono, H., Saito, I., and Kawatsuki, N., Appl. Phys. Lett. 72, 1942–44 (1998).Google Scholar
10 Lundquist, P. M., Wortmann, R., Geletneky, C., Twieg, R. J., Jurich, M., Lee, V. Y., Moylan, C. R., and Burland, D. M., Science 274, 1182–85 (1996).Google Scholar
11 Khoo, I. C., Slussarenko, S., Guenther, B. D., Shih, M.-Y., Chen, P., and Wood, W. V., Opt Lett. 23, 253–255 (1998).Google Scholar
12 Rudenko, E. V. and Sukhov, A. V., JETP 78, 875–882 (1994).Google Scholar
13 Wang, Q., Wang, L. M., and Yu, L. P., J. Am. Chem. Soc. 120, 12860–12868 (1998).Google Scholar
14 Ono, H., Opt. Lett. 22, 1144–46 (1997).Google Scholar
15 Khoo, I. C., IEEE J. Quant. Elec. 32, 525–534 (1996).Google Scholar
16 Cipparrone, G., Mazzulla, A., and Simoni, F., Opt. Lett. 23, 1505(1998).Google Scholar
17 Tabiryan, N. V. and Umeton, C., J. Opt. Soc. Am. B 15, 1912–17 (1998).Google Scholar
18 Giuliano, C. R., Physics Today April, 27–35 (1981).Google Scholar
19 Gunter, P. and Huignard, J. P., Photorefractive Materials and Their Applications 1:Fundamental Phenomena (Springer-Verlag, Berlin, 1988).Google Scholar
20 Wiederrecht, G. P., Yoon, B. A., and Wasielewski, M. R., Adv. Mat. 8, 535–39 (1996).Google Scholar
21 Moerner, W. E., A. Grunnet-Jepsen, and Thompson, C. L., Annu. Rev. Mater. Sci. 27, 585–623 (1997).Google Scholar
22 Gunter, P., Phys. Rep. 93, 199–299 (1982).Google Scholar
23 Maximus, B., Ley, E. D., Meyere, A. D., and Pauwels, H., Ferroelectrics 121, 103–112 (1991).Google Scholar
24 Wang, B. and Wasielewski, M. R., J. Am. Chem. Soc. 119, 12–21 (1997).Google Scholar
25 Greenfield, S. R., Svec, W. A., Gosztola, D., and Wasielewski, M. R., J Am. Chem. Soc. 118, 6767–6777 (1996).Google Scholar
26 The oxidation potentials, Eox of BEH-PPV and 5PV are both 0.9 V vs SCE, respectively, while their lowest excited state energies, Es are 2.4 eV and 2.7 eV, respectively. The reduction potential, ERED of NI is -0.5 V vs SCE. ΔG for photoinduced electron transfer is estimated as Eox – ERED – Es.Google Scholar
27 5PV was prepared by Wittig reaction of two moles of benzyltriphenylphosphonium bromide with the terminal dialdehyde of the corresponding three unit phenylenevinylene oligomer reported earlier.24 Google Scholar
28 Khoo, I. C., Opt. Lett. 20, 2137–39 (1995).Google Scholar
29 Wang, Q., Brubaker, R. M., Nolte, D. D., and Melloch, M. R., J Opt. Soc. Am. B 9, 1626–41(1992).Google Scholar
30 BraggRegime,.Google Scholar
31 Wiederrecht, G. P., Yoon, B. A., and Wasielewski, M. R., Synth. Met. 84, 901–2 (1997).Google Scholar
32 Hoofman, R. J. O. M., Haas, M. P. D., Siebbeles, L. D. A., and Warman, J. M., Nature 392, 54–56 (1998).Google Scholar
33 Davis, W. B., Svec, W. A., Ratner, M. A., and Wasielewski, M. R., Nature 396, 60–63(1998).Google Scholar
34 Levanon, H., Chem. Phys. Lett. 90, 465–71 (1982).Google Scholar
35 Ballauff, M., Angew. Chem. Int. Ed. Engl. 28, 253–267 (1989).Google Scholar
36 Wegner, G., Thin Solid Films 216, 105–116 (1992).Google Scholar
37 Lauter, U., Meyer, W. H., and Wegner, G., Macromolecules 30, 2092–2101 (1997).Google Scholar
38 Michaeli, S., Hugerat, M., Levanon, H., Bemitz, M., Natt, A., and Neumann, R., J Am.Chem. Soc. 114, 3612–18 (1992).Google Scholar