Resonant cavity coatings

Resonant Cavity Coatings. The thinnest and least costly acoustic coatings are of the resonant cavity design, as illustrated in Figure 4. Such coatings are rubber... 

Figure 4. Illustrative drawing of the cross-section of a typical resonant cavity coating.

The formation of periodical structures in the nanoscale is a busy field in the physics of materials. Submicrometer stractured materials have, and are expected to have, various apphcations [1 ], like optical filters and gratings, an-tireflective surface coatings, high density data storage, selective solar absorbers, microelectronics, optical switches, waveguides with low lost, chemical and biochemical sensors and resonant cavities for small lasers. 

Both the nitroxide decay measuranents of free-radical photoinitiation rates and nitroxide kinetics during HALS stabilization depend on accurate, quantitative measurements of nitroxide concentrations in cross-linked polymers. Quantification of radical concentrations by ESR requires a suitable primary standard, careful sample preparation, a reference standard with which to monitor spectrometer performance, and most important, reproducible positioning of the samples in the resonance cavity of the spectrometer. Most of the experiments described here were carried out with a Bruker-IBM ER 200 D spectrometer equipped with an Aspect 2000 Data System. Because these coatings are cured at temperatures as high as 130°C, the primary nitroxide standard, which was introduced into the coating prior to cure, had to be... 

The presence of the HRI coating induces an increase in the effective refractive index of the cladding modes and thus a decrease in the resonance wavelengths. In addition, the spatial shift of the cladding mode field profile toward the HRI overlay promotes a decrease of the overlap integral with the core mode and so of the transmission loss peak. The subsequent evaporation of the solvent molecules from the nano-cavities results in a reduction of its refractive index. This explains the partial... 

Figure 5. Thin rubber coating with resonant macroscopic cavities. The dashed lines show motion at the cavity walls.

---