Waveguide design

The other platform is dielectrics, for example, silicon dioxide, silicon nitride, silicon oxynitride, tantalum pentoxide, and titanium dioxide. They can be deposited by various methods, such as plasma-enhanced chemical vapor deposition, thermal evaporation, electron-beam evaporation, and sputtering. There are a number of dielectrics with refractive indices ranging from 1.45 to 2.4, facilitating diverse waveguide designs to satisfy different specification. Dielectrics have two other... 

OADM), there the step from waveguide design to system design is to be ineluded, neeessarily, and a change of the abstraetion level is required. 

Fig. 13 shows an example where data for an irregular struetured multilayer thin-film-filter (TFF) are imported into a waveguide design. A FDTD-simulation earned out in order to check the influence of the internal resonator-like strueture of the TFF onto the waveguide deviee shows a signifieant transversal shift for oblique incidence. This hinders symmetrical multi-port designs, but may be used for specific WDM functionality. ... 

A variety of additional properties and requirements must be demonstrated before such films are useful for devices. Waveguide designs require layers in the 0.1- to 1-jim thickness range. The films must be thermally stable, a property that is not a trivial matter for these waxy materials. It must also have photochemical and chemical stability in the environment in which it is used. The solution to these problems will require significant advances in synthetic and polymer chemistry. 

To assess the potential impact of polymeric and LB films on waveguide design and performance for SHG, I have examined the limitations imposed by phase-matching requirements on the interaction length needed to achieve a desired degree of conversion eflSciency. 

Operation of the sensor is identical to that of the planar waveguide design described above. 

In many cases the contribution from the first derivative dominates and the second term can be neglected. This case is referred to as critical phase matching. However, using a careful waveguide design, it is sometimes possible to cancel the first term by requiring that that the first derivative vanishes [Aj8 (/ o) 0]. This noncritical phase matching is very desirable, because it eases the acceptable tolerances. 

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