Polymer waveguides: characterization through prism–film coupler method

Abstract

Cr(VI) and Fe(III) doped polyvinyl alcohol) and poly(acrylic acid) polymers have been used as real-time holographic recording media as well as materials to fabricate planar waveguides. Planar wave guides were made of these metal ion doped polymer thin films. Changes in the absorption spectra of these polymer films due to irradiation with an intense illumination of 468 nm light were observed. Modifications in optical properties of dichromated poly(vinyl alcohol) (DCPVA), dichromated poly(acrylic acid) (DCPAA), and ferric chloride doped polyvinyl alcohol) (FePVA) were experimentally determined by the prism–film coupler (PFC) method for the first time. Changes in the refractive index at 632.8 nm were monitored for different exposure energies. Modification of the modal properties was observed and the refractive index of these films was also determined from the angular position of the guided modes. Optical losses in both exposed and unexposed films of DCPVA, DCPAA, and FePVA were measured employing a coupling set-up with two prisms. Observed results suggest that these materials can find successful applications in promising areas like integrated optics and planar optical interconnects.