Fluorinated-deuterated PMMA

Figure 3. Loss spectrum of fluorinated/deuterated PMMA waveguide.

Deuteration or fluorination will be needed even for NLO waveguides. It is necessary to fabricate channel waveguides with low loss to make NLO polymer devices such as phase modulators that can be driven with low input power. To this end, a deuterated 3RDCVXY polymer was developed for device application its chemical structure is shown in Figure 3.12(b) [48]. This polymer is composed of 3RDCVXY-attached PMMA and a transparent PMMA where all the hydrogen atoms are deuterated. 

As the main part of the GI-POFs is composed of PMMA, the loss spectrum is nearly the same as that of SI-POF with PMMA core. The attenuation loss of GI-POF with the gel-copolymerization technique at 652 nm is 134 dB/kra Koike s group, Keio University, has used an interfacial-gel-polymerization technique where bro-mobenzene or other chemicals are used as unreactive components instead of vinyl phenyl acetate or vinyl benzoate in the interfacial-gel-copolymerization method. An attenuation loss of 90 dB/km at 572 nm was obtained. MMA-dg was also used as a monomer instead of MMA, and the deuterated polymer core GI-POF was successfully fabricated. Fluorinated acrylate monomer was also used to fabricate moisture-resistant GI-POF. Attenuation losses of 113 and 155 dB/km at 780 nm wavelength were obtained for deuterated and fluorinated POFs, respectively. These POFs are Oj pected to serve as the signal transmission medium with high information capacities in local area network systems. However, this GI-POF has not been commercially available so far because of the fabrication difficulty of the technique in a mass production level with reasonable attenuation loss and fabrication cost. 

Figure 7.16 Loss spectrum for deuterated-fluorinated PMMA waveguide. (From Imamura, S., etal., Electron. Lett., 27, 1342, 1991. With permission.)... 

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