Planar omnidirectional reflectors in chalcogenide glass and polymer.

We have fabricated and tested planar reflectors exhibiting an omnidirectional stop band centered near 1750 nm wavelength. The reflectors are comprised of multiple layers of Ge33As12Se55 chalcogenide glass and polyamide-imide polymer. Glass layers were deposited by thermal evaporation and polymer layers were deposited by spin-casting. Thin film stacks of up to 13 layers showed good planarity and adhesion, which we attribute to the well-matched thermo-mechanical properties of the materials. The optical properties of the reflectors were tested in both transmission and reflection, and the results are in good agreement with theoretical predictions. Relatively low-temperature processing steps were employed, making these reflectors of interest for integrated optics.