Optical dielectric loss problems

What is to be noticed, finally, is the fact that different FEM-schemes may impose restrictions to the dielectric constant, e.g. they may require loss-less materials or a specific structure of the -tensor. Sometimes, FEM-problems are posed the way that eigen-frequencies for specified are computed, which is less common to the optical design process. Nevertheless, a special advantage of FE-based grids is the fact, that almost any complicated geometry can be included easily into standard triangulation schemes. 

Measurements of the dielectric response from the optical properties and plasmon losses have similar problems. 

Sol-gel and PU oligomerization reactions require a strict control of the reaction conditions, because atmospheric moisture can negatively influence the reaction, causing phase separation and optical loss. To tackle this problem, a new cross-linking unit, trifluorovinyl ether (TFVE), has been introduced. TFVE-containing monomeric units can be converted into perfluorocyclobutane (PFCB) containing polymers by a radical-mediated thermal cyclopolymerization reaction. These polymers have excellent properties such as a low dielectric constant, good thermal stability, and optical transparency [99]. 

The theory of themulti layer optical problem of the SBSC structure has been described in the literature. For single layer dielectric coatings on silicon the optimum refractive index is 2.1 - 2.4. Coatings with refractive indices within this region lead to practically identical results with theoretical reflection losses as low at 6% for both Si and GaAs substrates. 

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