Abstract

The photorefractivity of an indole derivative and of its polymer blends has been studied at room temperature. The indole derivative 3-[2-(4-nitrophenyl)ethenyl]-1-(2-ethylhexyl)-2-methylindole (NPEMI-E) is a typical low-molecular-weight glass-forming molecule having peculiar nonlinear optics characteristics. It is unconditionally soluble in the photoconductive poly-(N-vinyl-2,3-dimethylindole) so that all the possible blends can be studied for a weight percent (wt. %) content of NPEMI-E ranging from zero to 100. A very high and sharp maximum of the photorefractive optical gain Γ22000cm1 was obtained for a NPEMI-E wt. % content of about 90. On the basis of recently published theoretical calculations, we have made the hypothesis that the rapid change of Γ2 can also be ascribed to a correspondingly quick variation of the molecular electro-optic parameters of the dissolved chromophore for some well distinguished values of its concentration in the polymer matrix. Differential scanning calorimetry measurements were made and the results carefully analyzed with the aim of obtaining information on the intermolecular interactions. These last measurements also allowed rationalizing the unconditionally stable glass appearance of the obtained blends. Measurements of spectroscopic ellipsometry were also made on blends with different NPEMI-E content.

© 2008 Optical Society of America

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2006 (2)

R. Angelone, M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “An indole-based low molecular weight glass-former giving materials with high cooperative photorefractive optical gain,” Proc. SPIE 6192, 61922M (2006).

M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “Photorefractivity of poly-N-vinylindole-based materials as compared with that of poly-N-vinylcarbazole-based blends,” Appl. Opt. 45, 7928-7937(2006).
[CrossRef]

2005 (1)

F. Terenziani and A. Painelli, “Collective and cooperative phenomena in molecular materials: dimers of polar chromophores,” J. Lumin. 112, 474-478 (2005).

2004 (3)

A. Painelli and F. Terenziani, “Along the way from molecules to devices. The role of supramolecular interactions,” Synth. Met. 147, 111-115 (2004).

R. Angelone, C. Castè, V. Castelvetro, F. Ciardelli, A. Colligiani, F. Greco, A. Mazzotta, and G. Ruggeri, “Synthesis and electro-optical characterization of polysiloxanes containing indolyl groups acting as photoconductive substrates for photorefractive materials,” e-polymers 075, 1-15 (2004).

O. Ostroverkhova and W. E. Moerner, “Organic photorefractives: mechanisms, materials, and applications,” Chem. Rev. 104, 3267-3314 (2004).
[CrossRef]

2003 (7)

M. Drobizhev, A. Karotki, Y. Dzenis, A. Rebane, Z. Suo, and C. W. Spangler,“ Strong cooperative enhancement of two-photon absorption in dendrimers,” J. Phys. Chem. B 107, 7540-7543 (2003).

A. Abbotto, L. Beverina, R. Bozio, A. Facchetti, C. Ferrante, G. A. Pagani, D. Pedron, and R. Signorini,” Novel heteroaromatic-based multi-branched dyes with enhanced two-photon absorption activity,” Chem. Commun. 17, 2144-2145 (2003).

F. Stellacci, C. A. Bauer, T. Meyer-Friedrichsen, W. Wenseleers, S. R. Marder, and J. W. Perry, “Ultrabright supramolecular beacons based on the self-assembly of two-photon chromophores on metal nanoparticles,” J. Am. Chem. Soc. 125, 328-329 (2003).
[CrossRef]

C. Castè, V. Castelvetro, F. Ciardelli, A. Colligiani, A. Mazzotta, D. Michelotti, G. Ruggeri, and C. A. Veracini, “Photoconductive films of poly-N-vinylindole-based blends for high-voltage photorefractive electrooptic cells,” Synth. Met. 138, 341-345 (2003).
[CrossRef]

F. Terenziani and A. Painelli, “Supramolecular interactions in clusters of polar and polarizable molecules,” Phys. Rev. B 68, 165405 (2003).

A. Painelli and F. Terenziani, “Multielectron transfer in clusters of polar-polarizable chromophores,” J. Am. Chem. Soc. 125, 5624-5625 (2003).
[CrossRef]

O. Ostroverkhova, M. He, R. J. Twieg, and W. E. Moerner, “Role of temperature in controlling performance of photorefractive organic glasses,” Chem. Phys. Chem. 4, 732-744(2003).
[CrossRef]

2002 (2)

F. Würthner, R. Wortmann, and K. Meerholz, “Chromophore design for photorefractive organic materials,” Chem. Phys. Chem. 3, 17-31 (2002).
[CrossRef]

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

2001 (3)

D. J. Binks, K. Khand, and D. P. West, “Reorientation of chromophores in dispersive photorefractive polymers,” J. Opt. Soc. Am. B 18, 308-312 (2001).
[CrossRef]

F. Würthner, S. Yao, J. Schilling, R. Wortmann, M. Redi-Abshiro, E. Mecher, F. Gallego-Gomez, and K. Meerholz, “ATOP Dyes. Optimization of a multifunctional merocyanine chromophore for high refractive index modulation in photorefractive materials,” J. Am. Chem. Soc. 123, 2810-2824 (2001).
[CrossRef]

F. Brustolin, V. Castelvetro, F. Ciardelli, G. Ruggeri, and A. Colligiani, “Synthesis and characterization of different poly(1-vinylindole)s for photorefractive materials,” J. Polym. Sci. A Polym. Chem. 39, 253-262 (2001).

2000 (5)

A. Colligiani, F. Brustolin, V. Castelvetro, F. Ciardelli, and G. Ruggeri, “Poly(1-vinylindole) and some of its methyl derivatives as substrates for photorefractive materials: their synthesis, optical and electrical characterization,” Proc. SPIE 4104, 71-77 (2000).

D. Van Steenwinckel, E. Hendrickx, A. Persoons, K. Van den Broeck, and C. Samyn, “Influence of the chromophore ionization potential on speed and magnitude of photorefractive effects in poly(N-vinylcarbazole) based polymer composites,” J. Chem. Phys. 112, 11030-11037 (2000).
[CrossRef]

T. K. Däubler, R. Bittner, K. Meerholz, V. Cimrová, and D. Neher, “Charge carrier photogeneration, trapping, and space-charge field formation in PVK-based photorefractive materials,” Phys. Rev. B 61, 13515-13527 (2000).

F. Würthner and S. Yao, “Dipolar dye aggregates: a problem for nonlinear optics, but a chance for supramolecular chemistry,” Angew. Chem., Int. Ed. 39, 1978-1981 (2000).

H. Moon, J. Hwang, N. Kim, and S. Y. Park, “Synthesis and properties of photorefractive polymers containing indole-based multifunctional chromophore as a pendant group,” Macromolecules 33, 5116-5123 (2000).
[CrossRef]

1999 (2)

R. Bittner, T. K. Däubler, D. Neher, and K. Meerholz, “Influence of glass-transition temperature and chromophore content on the steady-state performance of poly(N-vinylcarbazole)-based photorefractive polymers,” Adv. Mater. 11, 123-127 (1999).
[CrossRef]

S. J. Chung, K. S. Kim, T. C. Lin, G. S. He, J. Swiatkiewicz, and P. N. Prasad, “Cooperative enhancement of two-photon absorption in multi-branched structures,” J. Phys. Chem. B 103, 10741-10745 (1999).
[CrossRef]

1998 (1)

1997 (1)

K. Meerholz, R. Bittner, Y. De Nardin, C. Bräuchle, E. Hendrickx, B. L. Volodin, B. Kippelen, and N. Peyghambarian, “Stability improvement of high-performance photorefractive polymers containing eutectic mixtures of electro-optic chromophores,” Adv. Mater. 9, 1043-1046 (1997).
[CrossRef]

1996 (1)

1995 (1)

R. H. Young, J. A. Sinicropi, and J. J. Fitzgerald, “Dipole moments, energetic disorder, and charge-transport in molecularly doped polymers,” J. Phys. Chem. 99, 9497-9506 (1995).
[CrossRef]

1994 (2)

1993 (4)

C. H. Wang, “Effects of the orientational pair correlation on second order nonlinear optical coefficients,” J. Chem. Phys. 98, 3457-3462 (1993).
[CrossRef]

M. C. Righetti, G. Ajroldi, G. Marchionni, and G. Pezzin, “Peculiarities of the glass transition temperature of binary polymeric systems: entropic and enthalpic treatments,” Polymer 34, 4307-4313 (1993).
[CrossRef]

H. Bässler, “Charge transport in disordered organic photoconductors: a Monte Carlo simulation study,” Phys. Status Solidi B 175, 15-56 (1993).
[CrossRef]

H. Bässler, “Charge-transport in random organic photoconductors,” Adv. Mater. 5, 662-665 (1993).
[CrossRef]

1992 (2)

X. Lu and R. A. Weiss, “Relationship between the glass transition temperature and the interaction parameter of miscibly binary polymer blends,” Macromolecules 25, 3242-3246 (1992).
[CrossRef]

M. C. Righetti, G. Ajroldi, and G. Pezzin, “The glass transition temperature of polymer-diluent systems,” Polymer 33, 4779-4785 (1992).
[CrossRef]

1991 (2)

P. R. Couchman, “Interaction Strength, nonrandom mixing, and the compositional variation of glass transition temperatures,” Macromolecules 24, 5772-5774 (1991).
[CrossRef]

P. M. Borsenberger, L. Pautmeier, and H. Bässler, “Charge transport in disordered molecular solids,” J. Chem. Phys. 94, 5447-5554 (1991).
[CrossRef]

1989 (1)

H. A. Schneider, “Glass transition behaviour of compatible polymer blends,” Polymer 30, 771-779 (1989).
[CrossRef]

1988 (1)

M. J. Brekner, H. A. Schneider, and H. J. Cantow, “Approach to the composition dependence of the glass transition temperature of compatible polymer blends: 1,” Polymer 29, 78-85(1988).
[CrossRef]

1984 (1)

D. M. Pai, J. F. Yanus, and M. Stolka, “Trap controlled hopping transport,” J. Phys. Chem. 88, 4714-4717 (1984).
[CrossRef]

1982 (1)

R. A. Marcus and P. J. Siders, “Theory of highly exothermic electron transfer reactions,” J. Phys. Chem. 86, 622-630(1982).
[CrossRef]

1978 (2)

P. R. Couchman and P. E. Karasz, “A classical thermodynamic discussion of the effect of composition on glass-transition temperatures,” Macromolecules 11, 117-119 (1978).
[CrossRef]

P. R. Couchman, “Compositional variation of glass-transition temperatures. 2. Application of the thermodynamic theory to compatible polymer blends,” Macromolecules 11, 1156-1161(1978).
[CrossRef]

1976 (1)

U. Landman, A. Ledwith, D. G. Marsh, and D. G. Williams, “Structural variations and multiple charge transfer transitions between chloranil and carbazole derivatives,” Macromolecules 9, 833-839 (1976).
[CrossRef]

1952 (1)

M. Gordon and J. S. Taylor, “Ideal copolymers and the second-order transitions of synthetic rubbers. I. NoN-crystalline copolymers,” J. Appl. Chem. 2, 493-500 (1952).

Abbotto, A.

A. Abbotto, L. Beverina, R. Bozio, A. Facchetti, C. Ferrante, G. A. Pagani, D. Pedron, and R. Signorini,” Novel heteroaromatic-based multi-branched dyes with enhanced two-photon absorption activity,” Chem. Commun. 17, 2144-2145 (2003).

Ajroldi, G.

M. C. Righetti, G. Ajroldi, G. Marchionni, and G. Pezzin, “Peculiarities of the glass transition temperature of binary polymeric systems: entropic and enthalpic treatments,” Polymer 34, 4307-4313 (1993).
[CrossRef]

M. C. Righetti, G. Ajroldi, and G. Pezzin, “The glass transition temperature of polymer-diluent systems,” Polymer 33, 4779-4785 (1992).
[CrossRef]

Angelone, R.

R. Angelone, M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “An indole-based low molecular weight glass-former giving materials with high cooperative photorefractive optical gain,” Proc. SPIE 6192, 61922M (2006).

R. Angelone, C. Castè, V. Castelvetro, F. Ciardelli, A. Colligiani, F. Greco, A. Mazzotta, and G. Ruggeri, “Synthesis and electro-optical characterization of polysiloxanes containing indolyl groups acting as photoconductive substrates for photorefractive materials,” e-polymers 075, 1-15 (2004).

R. Angelone, (personal communication, 2007).

Angiuli, M.

R. Angelone, M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “An indole-based low molecular weight glass-former giving materials with high cooperative photorefractive optical gain,” Proc. SPIE 6192, 61922M (2006).

M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “Photorefractivity of poly-N-vinylindole-based materials as compared with that of poly-N-vinylcarbazole-based blends,” Appl. Opt. 45, 7928-7937(2006).
[CrossRef]

Bässler, H.

H. Bässler, “Charge transport in disordered organic photoconductors: a Monte Carlo simulation study,” Phys. Status Solidi B 175, 15-56 (1993).
[CrossRef]

H. Bässler, “Charge-transport in random organic photoconductors,” Adv. Mater. 5, 662-665 (1993).
[CrossRef]

P. M. Borsenberger, L. Pautmeier, and H. Bässler, “Charge transport in disordered molecular solids,” J. Chem. Phys. 94, 5447-5554 (1991).
[CrossRef]

Bauer, C. A.

F. Stellacci, C. A. Bauer, T. Meyer-Friedrichsen, W. Wenseleers, S. R. Marder, and J. W. Perry, “Ultrabright supramolecular beacons based on the self-assembly of two-photon chromophores on metal nanoparticles,” J. Am. Chem. Soc. 125, 328-329 (2003).
[CrossRef]

Beljonne, D.

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

Beverina, L.

A. Abbotto, L. Beverina, R. Bozio, A. Facchetti, C. Ferrante, G. A. Pagani, D. Pedron, and R. Signorini,” Novel heteroaromatic-based multi-branched dyes with enhanced two-photon absorption activity,” Chem. Commun. 17, 2144-2145 (2003).

Binks, D. J.

Bittner, R.

T. K. Däubler, R. Bittner, K. Meerholz, V. Cimrová, and D. Neher, “Charge carrier photogeneration, trapping, and space-charge field formation in PVK-based photorefractive materials,” Phys. Rev. B 61, 13515-13527 (2000).

R. Bittner, T. K. Däubler, D. Neher, and K. Meerholz, “Influence of glass-transition temperature and chromophore content on the steady-state performance of poly(N-vinylcarbazole)-based photorefractive polymers,” Adv. Mater. 11, 123-127 (1999).
[CrossRef]

R. Bittner, C. Bräuchle, and K. Meerholz, “Influence of the glass-transition temperature and the chromophore content on the grating buildup dynamics of poly(N-vinylcarbazole)-based photorefractive polymers,” Appl. Opt. 37, 2843-2851 (1998).
[CrossRef]

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A. Colligiani, F. Brustolin, V. Castelvetro, F. Ciardelli, and G. Ruggeri, “Poly(1-vinylindole) and some of its methyl derivatives as substrates for photorefractive materials: their synthesis, optical and electrical characterization,” Proc. SPIE 4104, 71-77 (2000).

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A. Colligiani, F. Brustolin, V. Castelvetro, F. Ciardelli, and G. Ruggeri, “Poly(1-vinylindole) and some of its methyl derivatives as substrates for photorefractive materials: their synthesis, optical and electrical characterization,” Proc. SPIE 4104, 71-77 (2000).

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A. Abbotto, L. Beverina, R. Bozio, A. Facchetti, C. Ferrante, G. A. Pagani, D. Pedron, and R. Signorini,” Novel heteroaromatic-based multi-branched dyes with enhanced two-photon absorption activity,” Chem. Commun. 17, 2144-2145 (2003).

Perry, J. W.

F. Stellacci, C. A. Bauer, T. Meyer-Friedrichsen, W. Wenseleers, S. R. Marder, and J. W. Perry, “Ultrabright supramolecular beacons based on the self-assembly of two-photon chromophores on metal nanoparticles,” J. Am. Chem. Soc. 125, 328-329 (2003).
[CrossRef]

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

Persoons, A.

D. Van Steenwinckel, E. Hendrickx, A. Persoons, K. Van den Broeck, and C. Samyn, “Influence of the chromophore ionization potential on speed and magnitude of photorefractive effects in poly(N-vinylcarbazole) based polymer composites,” J. Chem. Phys. 112, 11030-11037 (2000).
[CrossRef]

Peyghambarian, N.

K. Meerholz, R. Bittner, Y. De Nardin, C. Bräuchle, E. Hendrickx, B. L. Volodin, B. Kippelen, and N. Peyghambarian, “Stability improvement of high-performance photorefractive polymers containing eutectic mixtures of electro-optic chromophores,” Adv. Mater. 9, 1043-1046 (1997).
[CrossRef]

Sandalphon, B. Kippelen, K. Meerholz, and N. Peyghambarian, “Ellipsometric measurements of poling birefringence, the Pockels effect and the Kerr effect in high performance photorefractive polymer composites,” Appl. Opt. 35, 2346-2354 (1996).
[CrossRef]

Pezzin, G.

M. C. Righetti, G. Ajroldi, G. Marchionni, and G. Pezzin, “Peculiarities of the glass transition temperature of binary polymeric systems: entropic and enthalpic treatments,” Polymer 34, 4307-4313 (1993).
[CrossRef]

M. C. Righetti, G. Ajroldi, and G. Pezzin, “The glass transition temperature of polymer-diluent systems,” Polymer 33, 4779-4785 (1992).
[CrossRef]

Pond, S. J. K.

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

Prasad, P. N.

S. J. Chung, K. S. Kim, T. C. Lin, G. S. He, J. Swiatkiewicz, and P. N. Prasad, “Cooperative enhancement of two-photon absorption in multi-branched structures,” J. Phys. Chem. B 103, 10741-10745 (1999).
[CrossRef]

P. N. Prasad and D. J. Williams, Introduction to NLO Effect in Molecules and Polymers (Wiley, 1991).

Rebane, A.

M. Drobizhev, A. Karotki, Y. Dzenis, A. Rebane, Z. Suo, and C. W. Spangler,“ Strong cooperative enhancement of two-photon absorption in dendrimers,” J. Phys. Chem. B 107, 7540-7543 (2003).

Redi-Abshiro, M.

F. Würthner, S. Yao, J. Schilling, R. Wortmann, M. Redi-Abshiro, E. Mecher, F. Gallego-Gomez, and K. Meerholz, “ATOP Dyes. Optimization of a multifunctional merocyanine chromophore for high refractive index modulation in photorefractive materials,” J. Am. Chem. Soc. 123, 2810-2824 (2001).
[CrossRef]

Righetti, M. C.

M. C. Righetti, G. Ajroldi, G. Marchionni, and G. Pezzin, “Peculiarities of the glass transition temperature of binary polymeric systems: entropic and enthalpic treatments,” Polymer 34, 4307-4313 (1993).
[CrossRef]

M. C. Righetti, G. Ajroldi, and G. Pezzin, “The glass transition temperature of polymer-diluent systems,” Polymer 33, 4779-4785 (1992).
[CrossRef]

Romano, A.

M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “Photorefractivity of poly-N-vinylindole-based materials as compared with that of poly-N-vinylcarbazole-based blends,” Appl. Opt. 45, 7928-7937(2006).
[CrossRef]

R. Angelone, M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “An indole-based low molecular weight glass-former giving materials with high cooperative photorefractive optical gain,” Proc. SPIE 6192, 61922M (2006).

Ruggeri, G.

R. Angelone, M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “An indole-based low molecular weight glass-former giving materials with high cooperative photorefractive optical gain,” Proc. SPIE 6192, 61922M (2006).

M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “Photorefractivity of poly-N-vinylindole-based materials as compared with that of poly-N-vinylcarbazole-based blends,” Appl. Opt. 45, 7928-7937(2006).
[CrossRef]

R. Angelone, C. Castè, V. Castelvetro, F. Ciardelli, A. Colligiani, F. Greco, A. Mazzotta, and G. Ruggeri, “Synthesis and electro-optical characterization of polysiloxanes containing indolyl groups acting as photoconductive substrates for photorefractive materials,” e-polymers 075, 1-15 (2004).

C. Castè, V. Castelvetro, F. Ciardelli, A. Colligiani, A. Mazzotta, D. Michelotti, G. Ruggeri, and C. A. Veracini, “Photoconductive films of poly-N-vinylindole-based blends for high-voltage photorefractive electrooptic cells,” Synth. Met. 138, 341-345 (2003).
[CrossRef]

F. Brustolin, V. Castelvetro, F. Ciardelli, G. Ruggeri, and A. Colligiani, “Synthesis and characterization of different poly(1-vinylindole)s for photorefractive materials,” J. Polym. Sci. A Polym. Chem. 39, 253-262 (2001).

A. Colligiani, F. Brustolin, V. Castelvetro, F. Ciardelli, and G. Ruggeri, “Poly(1-vinylindole) and some of its methyl derivatives as substrates for photorefractive materials: their synthesis, optical and electrical characterization,” Proc. SPIE 4104, 71-77 (2000).

Samyn, C.

D. Van Steenwinckel, E. Hendrickx, A. Persoons, K. Van den Broeck, and C. Samyn, “Influence of the chromophore ionization potential on speed and magnitude of photorefractive effects in poly(N-vinylcarbazole) based polymer composites,” J. Chem. Phys. 112, 11030-11037 (2000).
[CrossRef]

Sandalphon,

Schilling, J.

F. Würthner, S. Yao, J. Schilling, R. Wortmann, M. Redi-Abshiro, E. Mecher, F. Gallego-Gomez, and K. Meerholz, “ATOP Dyes. Optimization of a multifunctional merocyanine chromophore for high refractive index modulation in photorefractive materials,” J. Am. Chem. Soc. 123, 2810-2824 (2001).
[CrossRef]

Schneider, H. A.

H. A. Schneider, “Glass transition behaviour of compatible polymer blends,” Polymer 30, 771-779 (1989).
[CrossRef]

M. J. Brekner, H. A. Schneider, and H. J. Cantow, “Approach to the composition dependence of the glass transition temperature of compatible polymer blends: 1,” Polymer 29, 78-85(1988).
[CrossRef]

Shuai, Z. G.

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

Siders, P. J.

R. A. Marcus and P. J. Siders, “Theory of highly exothermic electron transfer reactions,” J. Phys. Chem. 86, 622-630(1982).
[CrossRef]

Signorini, R.

A. Abbotto, L. Beverina, R. Bozio, A. Facchetti, C. Ferrante, G. A. Pagani, D. Pedron, and R. Signorini,” Novel heteroaromatic-based multi-branched dyes with enhanced two-photon absorption activity,” Chem. Commun. 17, 2144-2145 (2003).

Silence, S.

W. E. Moerner and S. Silence, “Polymeric photorefractive materials,” Chem. Rev. 94, 127-155 (1994).
[CrossRef]

Silence, S. M.

Sinicropi, J. A.

R. H. Young, J. A. Sinicropi, and J. J. Fitzgerald, “Dipole moments, energetic disorder, and charge-transport in molecularly doped polymers,” J. Phys. Chem. 99, 9497-9506 (1995).
[CrossRef]

Spangler, C. W.

M. Drobizhev, A. Karotki, Y. Dzenis, A. Rebane, Z. Suo, and C. W. Spangler,“ Strong cooperative enhancement of two-photon absorption in dendrimers,” J. Phys. Chem. B 107, 7540-7543 (2003).

Stellacci, F.

F. Stellacci, C. A. Bauer, T. Meyer-Friedrichsen, W. Wenseleers, S. R. Marder, and J. W. Perry, “Ultrabright supramolecular beacons based on the self-assembly of two-photon chromophores on metal nanoparticles,” J. Am. Chem. Soc. 125, 328-329 (2003).
[CrossRef]

Stolka, M.

D. M. Pai, J. F. Yanus, and M. Stolka, “Trap controlled hopping transport,” J. Phys. Chem. 88, 4714-4717 (1984).
[CrossRef]

Suo, Z.

M. Drobizhev, A. Karotki, Y. Dzenis, A. Rebane, Z. Suo, and C. W. Spangler,“ Strong cooperative enhancement of two-photon absorption in dendrimers,” J. Phys. Chem. B 107, 7540-7543 (2003).

Swiatkiewicz, J.

S. J. Chung, K. S. Kim, T. C. Lin, G. S. He, J. Swiatkiewicz, and P. N. Prasad, “Cooperative enhancement of two-photon absorption in multi-branched structures,” J. Phys. Chem. B 103, 10741-10745 (1999).
[CrossRef]

Taylor, J. S.

M. Gordon and J. S. Taylor, “Ideal copolymers and the second-order transitions of synthetic rubbers. I. NoN-crystalline copolymers,” J. Appl. Chem. 2, 493-500 (1952).

Terenziani, F.

F. Terenziani and A. Painelli, “Collective and cooperative phenomena in molecular materials: dimers of polar chromophores,” J. Lumin. 112, 474-478 (2005).

A. Painelli and F. Terenziani, “Along the way from molecules to devices. The role of supramolecular interactions,” Synth. Met. 147, 111-115 (2004).

A. Painelli and F. Terenziani, “Multielectron transfer in clusters of polar-polarizable chromophores,” J. Am. Chem. Soc. 125, 5624-5625 (2003).
[CrossRef]

F. Terenziani and A. Painelli, “Supramolecular interactions in clusters of polar and polarizable molecules,” Phys. Rev. B 68, 165405 (2003).

Tombari, E.

R. Angelone, M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “An indole-based low molecular weight glass-former giving materials with high cooperative photorefractive optical gain,” Proc. SPIE 6192, 61922M (2006).

M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “Photorefractivity of poly-N-vinylindole-based materials as compared with that of poly-N-vinylcarbazole-based blends,” Appl. Opt. 45, 7928-7937(2006).
[CrossRef]

Twieg, R. J.

O. Ostroverkhova, M. He, R. J. Twieg, and W. E. Moerner, “Role of temperature in controlling performance of photorefractive organic glasses,” Chem. Phys. Chem. 4, 732-744(2003).
[CrossRef]

Van den Broeck, K.

D. Van Steenwinckel, E. Hendrickx, A. Persoons, K. Van den Broeck, and C. Samyn, “Influence of the chromophore ionization potential on speed and magnitude of photorefractive effects in poly(N-vinylcarbazole) based polymer composites,” J. Chem. Phys. 112, 11030-11037 (2000).
[CrossRef]

Van Krevelen, D. W.

D. W. Van Krevelen, Properties of Polymers (Elsevier, 1997).

Van Steenwinckel, D.

D. Van Steenwinckel, E. Hendrickx, A. Persoons, K. Van den Broeck, and C. Samyn, “Influence of the chromophore ionization potential on speed and magnitude of photorefractive effects in poly(N-vinylcarbazole) based polymer composites,” J. Chem. Phys. 112, 11030-11037 (2000).
[CrossRef]

Veracini, C. A.

C. Castè, V. Castelvetro, F. Ciardelli, A. Colligiani, A. Mazzotta, D. Michelotti, G. Ruggeri, and C. A. Veracini, “Photoconductive films of poly-N-vinylindole-based blends for high-voltage photorefractive electrooptic cells,” Synth. Met. 138, 341-345 (2003).
[CrossRef]

Vogel, H.

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

Volodin, B. L.

K. Meerholz, R. Bittner, Y. De Nardin, C. Bräuchle, E. Hendrickx, B. L. Volodin, B. Kippelen, and N. Peyghambarian, “Stability improvement of high-performance photorefractive polymers containing eutectic mixtures of electro-optic chromophores,” Adv. Mater. 9, 1043-1046 (1997).
[CrossRef]

Wang, C. H.

C. H. Wang, “Effects of the orientational pair correlation on second order nonlinear optical coefficients,” J. Chem. Phys. 98, 3457-3462 (1993).
[CrossRef]

Weiss, D. S.

P. M. Borsenberger and D. S. Weiss, Organic Photoreceptors for Xerography (Marcel Dekker, 1998), Vol. 59.

Weiss, R. A.

X. Lu and R. A. Weiss, “Relationship between the glass transition temperature and the interaction parameter of miscibly binary polymer blends,” Macromolecules 25, 3242-3246 (1992).
[CrossRef]

Wenseleers, W.

F. Stellacci, C. A. Bauer, T. Meyer-Friedrichsen, W. Wenseleers, S. R. Marder, and J. W. Perry, “Ultrabright supramolecular beacons based on the self-assembly of two-photon chromophores on metal nanoparticles,” J. Am. Chem. Soc. 125, 328-329 (2003).
[CrossRef]

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

West, D. P.

Williams, D. G.

U. Landman, A. Ledwith, D. G. Marsh, and D. G. Williams, “Structural variations and multiple charge transfer transitions between chloranil and carbazole derivatives,” Macromolecules 9, 833-839 (1976).
[CrossRef]

Williams, D. J.

P. N. Prasad and D. J. Williams, Introduction to NLO Effect in Molecules and Polymers (Wiley, 1991).

Wortmann, R.

F. Würthner, R. Wortmann, and K. Meerholz, “Chromophore design for photorefractive organic materials,” Chem. Phys. Chem. 3, 17-31 (2002).
[CrossRef]

F. Würthner, S. Yao, J. Schilling, R. Wortmann, M. Redi-Abshiro, E. Mecher, F. Gallego-Gomez, and K. Meerholz, “ATOP Dyes. Optimization of a multifunctional merocyanine chromophore for high refractive index modulation in photorefractive materials,” J. Am. Chem. Soc. 123, 2810-2824 (2001).
[CrossRef]

Würthner, F.

F. Würthner, R. Wortmann, and K. Meerholz, “Chromophore design for photorefractive organic materials,” Chem. Phys. Chem. 3, 17-31 (2002).
[CrossRef]

F. Würthner, S. Yao, J. Schilling, R. Wortmann, M. Redi-Abshiro, E. Mecher, F. Gallego-Gomez, and K. Meerholz, “ATOP Dyes. Optimization of a multifunctional merocyanine chromophore for high refractive index modulation in photorefractive materials,” J. Am. Chem. Soc. 123, 2810-2824 (2001).
[CrossRef]

F. Würthner and S. Yao, “Dipolar dye aggregates: a problem for nonlinear optics, but a chance for supramolecular chemistry,” Angew. Chem., Int. Ed. 39, 1978-1981 (2000).

Yanus, J. F.

D. M. Pai, J. F. Yanus, and M. Stolka, “Trap controlled hopping transport,” J. Phys. Chem. 88, 4714-4717 (1984).
[CrossRef]

Yao, S.

F. Würthner, S. Yao, J. Schilling, R. Wortmann, M. Redi-Abshiro, E. Mecher, F. Gallego-Gomez, and K. Meerholz, “ATOP Dyes. Optimization of a multifunctional merocyanine chromophore for high refractive index modulation in photorefractive materials,” J. Am. Chem. Soc. 123, 2810-2824 (2001).
[CrossRef]

F. Würthner and S. Yao, “Dipolar dye aggregates: a problem for nonlinear optics, but a chance for supramolecular chemistry,” Angew. Chem., Int. Ed. 39, 1978-1981 (2000).

Young, R. H.

R. H. Young, J. A. Sinicropi, and J. J. Fitzgerald, “Dipole moments, energetic disorder, and charge-transport in molecularly doped polymers,” J. Phys. Chem. 99, 9497-9506 (1995).
[CrossRef]

Zojer, E.

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

Adv. Funct. Mater. (1)

D. Beljonne, W. Wenseleers, E. Zojer, Z. G. Shuai, H. Vogel, S. J. K. Pond, J. W. Perry, S. R. Marder, and J. L. Bredas, “Role of dimensionality on the two-photon absorption response of conjugated molecules: the case of octupolar compounds,” Adv. Funct. Mater. 12, 631-641 (2002).
[CrossRef]

Adv. Mater. (3)

K. Meerholz, R. Bittner, Y. De Nardin, C. Bräuchle, E. Hendrickx, B. L. Volodin, B. Kippelen, and N. Peyghambarian, “Stability improvement of high-performance photorefractive polymers containing eutectic mixtures of electro-optic chromophores,” Adv. Mater. 9, 1043-1046 (1997).
[CrossRef]

R. Bittner, T. K. Däubler, D. Neher, and K. Meerholz, “Influence of glass-transition temperature and chromophore content on the steady-state performance of poly(N-vinylcarbazole)-based photorefractive polymers,” Adv. Mater. 11, 123-127 (1999).
[CrossRef]

H. Bässler, “Charge-transport in random organic photoconductors,” Adv. Mater. 5, 662-665 (1993).
[CrossRef]

Angew. Chem., Int. Ed. (1)

F. Würthner and S. Yao, “Dipolar dye aggregates: a problem for nonlinear optics, but a chance for supramolecular chemistry,” Angew. Chem., Int. Ed. 39, 1978-1981 (2000).

Appl. Opt. (3)

Chem. Commun. (1)

A. Abbotto, L. Beverina, R. Bozio, A. Facchetti, C. Ferrante, G. A. Pagani, D. Pedron, and R. Signorini,” Novel heteroaromatic-based multi-branched dyes with enhanced two-photon absorption activity,” Chem. Commun. 17, 2144-2145 (2003).

Chem. Phys. Chem. (2)

F. Würthner, R. Wortmann, and K. Meerholz, “Chromophore design for photorefractive organic materials,” Chem. Phys. Chem. 3, 17-31 (2002).
[CrossRef]

O. Ostroverkhova, M. He, R. J. Twieg, and W. E. Moerner, “Role of temperature in controlling performance of photorefractive organic glasses,” Chem. Phys. Chem. 4, 732-744(2003).
[CrossRef]

Chem. Rev. (2)

W. E. Moerner and S. Silence, “Polymeric photorefractive materials,” Chem. Rev. 94, 127-155 (1994).
[CrossRef]

O. Ostroverkhova and W. E. Moerner, “Organic photorefractives: mechanisms, materials, and applications,” Chem. Rev. 104, 3267-3314 (2004).
[CrossRef]

e-polymers (1)

R. Angelone, C. Castè, V. Castelvetro, F. Ciardelli, A. Colligiani, F. Greco, A. Mazzotta, and G. Ruggeri, “Synthesis and electro-optical characterization of polysiloxanes containing indolyl groups acting as photoconductive substrates for photorefractive materials,” e-polymers 075, 1-15 (2004).

J. Am. Chem. Soc. (3)

F. Stellacci, C. A. Bauer, T. Meyer-Friedrichsen, W. Wenseleers, S. R. Marder, and J. W. Perry, “Ultrabright supramolecular beacons based on the self-assembly of two-photon chromophores on metal nanoparticles,” J. Am. Chem. Soc. 125, 328-329 (2003).
[CrossRef]

F. Würthner, S. Yao, J. Schilling, R. Wortmann, M. Redi-Abshiro, E. Mecher, F. Gallego-Gomez, and K. Meerholz, “ATOP Dyes. Optimization of a multifunctional merocyanine chromophore for high refractive index modulation in photorefractive materials,” J. Am. Chem. Soc. 123, 2810-2824 (2001).
[CrossRef]

A. Painelli and F. Terenziani, “Multielectron transfer in clusters of polar-polarizable chromophores,” J. Am. Chem. Soc. 125, 5624-5625 (2003).
[CrossRef]

J. Appl. Chem. (1)

M. Gordon and J. S. Taylor, “Ideal copolymers and the second-order transitions of synthetic rubbers. I. NoN-crystalline copolymers,” J. Appl. Chem. 2, 493-500 (1952).

J. Chem. Phys. (3)

D. Van Steenwinckel, E. Hendrickx, A. Persoons, K. Van den Broeck, and C. Samyn, “Influence of the chromophore ionization potential on speed and magnitude of photorefractive effects in poly(N-vinylcarbazole) based polymer composites,” J. Chem. Phys. 112, 11030-11037 (2000).
[CrossRef]

P. M. Borsenberger, L. Pautmeier, and H. Bässler, “Charge transport in disordered molecular solids,” J. Chem. Phys. 94, 5447-5554 (1991).
[CrossRef]

C. H. Wang, “Effects of the orientational pair correlation on second order nonlinear optical coefficients,” J. Chem. Phys. 98, 3457-3462 (1993).
[CrossRef]

J. Lumin. (1)

F. Terenziani and A. Painelli, “Collective and cooperative phenomena in molecular materials: dimers of polar chromophores,” J. Lumin. 112, 474-478 (2005).

J. Opt. Soc. Am. B (2)

J. Phys. Chem. (3)

R. H. Young, J. A. Sinicropi, and J. J. Fitzgerald, “Dipole moments, energetic disorder, and charge-transport in molecularly doped polymers,” J. Phys. Chem. 99, 9497-9506 (1995).
[CrossRef]

R. A. Marcus and P. J. Siders, “Theory of highly exothermic electron transfer reactions,” J. Phys. Chem. 86, 622-630(1982).
[CrossRef]

D. M. Pai, J. F. Yanus, and M. Stolka, “Trap controlled hopping transport,” J. Phys. Chem. 88, 4714-4717 (1984).
[CrossRef]

J. Phys. Chem. B (2)

M. Drobizhev, A. Karotki, Y. Dzenis, A. Rebane, Z. Suo, and C. W. Spangler,“ Strong cooperative enhancement of two-photon absorption in dendrimers,” J. Phys. Chem. B 107, 7540-7543 (2003).

S. J. Chung, K. S. Kim, T. C. Lin, G. S. He, J. Swiatkiewicz, and P. N. Prasad, “Cooperative enhancement of two-photon absorption in multi-branched structures,” J. Phys. Chem. B 103, 10741-10745 (1999).
[CrossRef]

J. Polym. Sci. A Polym. Chem. (1)

F. Brustolin, V. Castelvetro, F. Ciardelli, G. Ruggeri, and A. Colligiani, “Synthesis and characterization of different poly(1-vinylindole)s for photorefractive materials,” J. Polym. Sci. A Polym. Chem. 39, 253-262 (2001).

Macromolecules (6)

X. Lu and R. A. Weiss, “Relationship between the glass transition temperature and the interaction parameter of miscibly binary polymer blends,” Macromolecules 25, 3242-3246 (1992).
[CrossRef]

P. R. Couchman and P. E. Karasz, “A classical thermodynamic discussion of the effect of composition on glass-transition temperatures,” Macromolecules 11, 117-119 (1978).
[CrossRef]

P. R. Couchman, “Compositional variation of glass-transition temperatures. 2. Application of the thermodynamic theory to compatible polymer blends,” Macromolecules 11, 1156-1161(1978).
[CrossRef]

P. R. Couchman, “Interaction Strength, nonrandom mixing, and the compositional variation of glass transition temperatures,” Macromolecules 24, 5772-5774 (1991).
[CrossRef]

U. Landman, A. Ledwith, D. G. Marsh, and D. G. Williams, “Structural variations and multiple charge transfer transitions between chloranil and carbazole derivatives,” Macromolecules 9, 833-839 (1976).
[CrossRef]

H. Moon, J. Hwang, N. Kim, and S. Y. Park, “Synthesis and properties of photorefractive polymers containing indole-based multifunctional chromophore as a pendant group,” Macromolecules 33, 5116-5123 (2000).
[CrossRef]

Phys. Rev. B (2)

T. K. Däubler, R. Bittner, K. Meerholz, V. Cimrová, and D. Neher, “Charge carrier photogeneration, trapping, and space-charge field formation in PVK-based photorefractive materials,” Phys. Rev. B 61, 13515-13527 (2000).

F. Terenziani and A. Painelli, “Supramolecular interactions in clusters of polar and polarizable molecules,” Phys. Rev. B 68, 165405 (2003).

Phys. Status Solidi B (1)

H. Bässler, “Charge transport in disordered organic photoconductors: a Monte Carlo simulation study,” Phys. Status Solidi B 175, 15-56 (1993).
[CrossRef]

Polymer (4)

M. C. Righetti, G. Ajroldi, and G. Pezzin, “The glass transition temperature of polymer-diluent systems,” Polymer 33, 4779-4785 (1992).
[CrossRef]

M. C. Righetti, G. Ajroldi, G. Marchionni, and G. Pezzin, “Peculiarities of the glass transition temperature of binary polymeric systems: entropic and enthalpic treatments,” Polymer 34, 4307-4313 (1993).
[CrossRef]

M. J. Brekner, H. A. Schneider, and H. J. Cantow, “Approach to the composition dependence of the glass transition temperature of compatible polymer blends: 1,” Polymer 29, 78-85(1988).
[CrossRef]

H. A. Schneider, “Glass transition behaviour of compatible polymer blends,” Polymer 30, 771-779 (1989).
[CrossRef]

Proc. SPIE (2)

R. Angelone, M. Angiuli, F. Ciardelli, A. Colligiani, F. Greco, A. Romano, G. Ruggeri, and E. Tombari, “An indole-based low molecular weight glass-former giving materials with high cooperative photorefractive optical gain,” Proc. SPIE 6192, 61922M (2006).

A. Colligiani, F. Brustolin, V. Castelvetro, F. Ciardelli, and G. Ruggeri, “Poly(1-vinylindole) and some of its methyl derivatives as substrates for photorefractive materials: their synthesis, optical and electrical characterization,” Proc. SPIE 4104, 71-77 (2000).

Synth. Met. (2)

C. Castè, V. Castelvetro, F. Ciardelli, A. Colligiani, A. Mazzotta, D. Michelotti, G. Ruggeri, and C. A. Veracini, “Photoconductive films of poly-N-vinylindole-based blends for high-voltage photorefractive electrooptic cells,” Synth. Met. 138, 341-345 (2003).
[CrossRef]

A. Painelli and F. Terenziani, “Along the way from molecules to devices. The role of supramolecular interactions,” Synth. Met. 147, 111-115 (2004).

Other (7)

P. M. Borsenberger and D. S. Weiss, Organic Photoreceptors for Xerography (Marcel Dekker, 1998), Vol. 59.

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P. J. Flory, Principles of Polymer Chemistry (Cornell U. Press, 1953).

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Figures (6)

Fig. 1
Fig. 1

Chemical structures of NPEMI-E and of the repetitive unit of PVDMI.

Fig. 2
Fig. 2

Dependence of the measured values of the glass-transition temperature T g (solid circles) on the composition of the studied blends. The results for various fitting procedures are also reported.

Fig. 3
Fig. 3

Trend of the measured photocurrent i ph as a function of both the composition of the different blends (lower axis) and of the reduced temperature T r (upper axis): solid circles, values at E = 60 V / μm ; solid triangles, values at E = 90 V / μm .

Fig. 4
Fig. 4

Trend of the measured photocurrent i ph of the studied blends as a function of the square root of the applied electric field E (Poole–Frenkel-like equation). The meaning of the symbols used is clearly specified in the insert. The results for NPE80 and NPE85 blends have not been reported.

Fig. 5
Fig. 5

Trend of the obtained photorefractive optical gain Γ 2 as a function of both the composition of the different blends (lower axis) and of the reduced temperature T r (upper axis): solid circles, values at E = 60 V / μm ; solid triangles, values at E = 90 V / μm . The maximum of both curves is at about a wt. % of 91.5.

Fig. 6
Fig. 6

Trend of the measured refractive index n 0 (solid circles), E = 0.0 V / μm , and Δ n (open circles), E = 30 V / μm as a function of the composition of the different blends, obtained by spectroscopic ellipsometry at λ = 685 nm . The broken line is only an aid for the eyes.

Tables (2)

Tables Icon

Table 1 Composition of the Studied Blends and Their Glass-Transition ( T g ) Temperatures a

Tables Icon

Table 2 Photocurrent i ph and Photorefractive Optical Gain Γ 2 of the Studied Blends as Measured at E = 60 V / μm and 90 V / μm a

Equations (7)

Equations on this page are rendered with MathJax. Learn more.

T g = ( w 1 T g 1 + K w 2 T g 2 ) / ( w 1 + K w 2 ) ,
m ( E ) = m ( 0 ) exp ( S E 1 / 2 ) .
F = ( 1 / M ) [ 9 μ β + μ 2 Δ α / k T ] .
Γ Δ n sin Φ .
tan Φ = E 0 / E q .
E q = e N T / k ε r .
| E SC | A { E 0 2 / [ 1 + ( E 0 / E q ) 2 ] } 1 / 2 .

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