Electro-optical polymer

Enami, Y. Peyghambarian, N. Kawazu, M. Jen, A. K. Y., Hybrid electro optic polymer and selectively buried sol gel waveguides, Appl. Phys. Lett. 2003, 82,490 492... 

Sinyukov, A. M. Hayden, L. M., Generation and detection of terahertz radiation with multilayered electro optic polymer films, Opt. Lett. 2002, 27, 55 57... 

The Wiley Series in Polymer Science aims to cover topics in polymer science where significant advances have been made over the past decade. Key features of the series will be developing areas and new frontiers in polymer science and technology. Emerging fields with strong growth potential for the twenty-first century such as nanotechnology, photopolymers, electro-optic polymers etc. will be covered. Additionally, those polymer classes in which important new members have appeared in recent years will be revisited to provide a comprehensive update. 

Note 3 A polymer that exhibits a nonlinear optical effect due to anisotropic electric susceptibilities when subjected to electric field together with light irradiation is called an electro-optical polymer. A polymer that exhibits electro-optical behavior combined with photoconductivity is called a photorefractive polymer. 

The application of electro-optic polymer materials to practical devices will require some significant advances in the development of the materials. The primary advance required is the achievement of suitable thermal stability of the poled state over temperature ranges determined by fabrication, assembly, and end use requirements. Table in illustrates some of the temperatures and conditions under which a poled polymer must remain poled to within a few percent of its initial value over the life of a device. 

The simple analysis presented above confirms that new formulations are required to produce stable, reliable products for field use. Practical system requirements, as defined by Mil Spec conformity and the use of standard fabrication and assembly processes, definitely require that a electro-optic polymer system with better thermal properties than thermoplastic acrylates be developed. That this is true for optical interconnection boards and modules is not surprising because of their complexity. It is perhaps remarkable that it remains true for even simple devices, such as a packaged, pigtailed traveling-wave modulator. The ultimate success of electro-optic polymers will be their use in cost-effective products that are used by systems designers. 

Lytel, R. Lipscomb, F. Electro-Optic Polymer Waveguide Devices Status and Applications, this volume... 

Three synthetic approaches to donor-acceptor-substituted conjugated molecules with enhanced orientability in electric fields, potentially applicable to the preparation of electro-optic polymers via electric field poling, are summarized. The three approaches are parallel attachment of chromophores to a common framework, embedding the chromophore in a zwitterion, and head-to-tail oligomerization of chromophores. The oligomerization method as well as the use of dyes as curing agents are briefly discussed in relation to the stability of electric field-induced polar order in polymer matrices. 

These materials may also be included in guest-host or side-chain polymer systems, similar to those exploited in electro-optic polymer studies. This would improve processability for waveguide devices. The coefficients quoted above show that such a doped polymer could function at reasonable power levels and waveguide dimensions with an active region 1-2 mm long. 

Fig. 40. Schematic representation of our electro-optic polymer beam steering device with a demonstration of its performance...

Lee MH, Lee HJ, Han SG, Kim HY, Won YH (1998) Fabrication and characterization of electro-optic polymer waveguide modulator for photonic application. In Wise DL, Wnek GE, Trantolo DJ, Cooper TM, Gresser JD (eds) Electrical and optical polymer systems. Marcel Dekker, New York, chap 17... 

Tondiglia, V., Natarajan, L., Sutherland, R. et al.. Holographic formation of electro-optical polymer-liquid crystal photonic crystals, Adv. Mater., 14, 187, 2002. 

To understand and optimize the electro-optic properties of polymers by the use of molecular engineering, it is of primary importance to be able to relate their macroscopic properties to the individual molecular properties. Such a task is the subject of intensive research. However, simple descriptions based on the oriented gas model exist [ 20,21 ] and have proven to be in many cases a good approximation for the description of poled electro-optic polymers [22]. The oriented gas model provides a simple way to relate the macroscopic nonlinear optical properties such as the second-order susceptibility tensor elements expressed in the orthogonal laboratory frame X,Y,Z, and the microscopic hyperpolarizability tensor elements that are given in the orthogonal molecular frame x,y,z (see Fig. 9). 

Sinyukov A.M., Hayden, L.M. Efficient electro-optic polymers for thz systems, J. Phys. Chem. B 108, 8515-8522 (2004)... 

As for purely electro-optic polymers the electro-optic functionality can be achieved in a variety of different ways including guest/host systems, side-chain and main-chain polymers, crosslinked polymers and self-assembly approaches (36-38). In amorphous polymers, the NLO chromophores which have a permanent dipole moment are oriented with an electric field to induce electro-optic effects (39). Orientation of these dipoles leads not only to macroscopic electro-optic properties but also to birefringence (40). In the oriented gas model and for a poling field applied along the Z axis these two effects can be described by (39) ... 

In this chapter, the development of NLO polymers with thin film or channel waveguide structures directed toward practical optical devices will be discussed. All optical signal processing polymers and electro-optical polymers are presented. Hybrid polymer optical devices for future applications will also be presented. 

Lee, M., H.E. Katz, C. Erben, D.M. Gill, P. Gopalan, J. D. Heber, and D.J. McGee. 2002. Ultra-fast modulation of light using an electro-optic polymer. Science 298 1401. 

Sinyukov, A.M., M.R. Leahy, L.M. Hayden, M. Haller, J. Luo, A.K.Y. Jen, and L.R. Dalton. 2004. Resonance enhanced THz generation in electro-optic polymers near the absorption maximum. Appl Phys Lett 85 5827-829. 

Song, H.C., M.C. Oh, S.W. Ahn, and W.H. Steier. 2003. Flexible low-voltage electro-optic polymer modulators. Appl Phys Lett 82 4432—4434. 

Paloczi, G.T., Y. Huang, A. Yariv, J. Luo, and A. Jen. 2004. Replica-molded electro-optic polymer Mach-Zehnder modulator. Appl Phys Lett 85 1662-1664. 

Taylor, E.W., J.E. Nichter, ED. Nash, F. Haas, A.A. Szep, R.J. Michalak, B.M. Flusche, P.R. Cook, T.A. McEwen, B.F. McKeon, P.M. Payson, G.A. Brost, A.R. Pirich, C. Castaneda, B. Tsap, and H.R. Fetterman. 2005. Radiation resistance of electro-optic polymer-based modulators. Appl Phys Lett 86 201122-1-3. 

Chang, D.H., T. Azfar, S.K. Kim, H.R. Fetterman, C. Zhang, and W.H. Steier. 2003. Vertical adiabatic transition between silica planar waveguide and electro-optic polymer fabricated using grayscale lithography. Opt Lett 28 869-871. 

Chen, A., V. Chuyanov, F.I. Marti-Carrera, S. Gamer, W.H. Steier, and L.R. Dalton. 1997. Fast trimming of electro-optic polymer waveguide Y-branch by post-photobleaching for tuning the power splitting ratio. Proc SPIE 3147 268-274. 

Lee, S.S., S. Gamer, A. Chen, V. Chuyanov, W.H. Steier, L. Guo, L.R. Dalton, and S.Y. Shin. 1998. Patterned birefringence by photo-induced de-poling in electro-optic polymers and its application to a waveguide polarization splitter. AppI Phys Lett 73 3052-3054. 

Pyajt, A., L. Dalton, and A. Chen. 2005. Novel wavelength selective switch based on electro-optic polymer microrings. Proc SPIE 5935 W1—14. 

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