title: Refractive index gratings in electro-optic polymer thin films.
abstract: Refractive index gratings have been inscribed in polymer thin films by permanently photobleaching the organic chromophore PYR-3 dopant. The grating inscription process was investigated in detail for the purpose of improving the diffraction efficiency (η) of the PYR-3 doped polymer gratings. Three processes were identified that contributed to the η of the first diffracted order: a periodic change in the refractive index due to photobleaching of the PYR-3, formation of the surface relief grating as a consequence of free volume change during bleaching, and the introduction of periodic, strain-induced changes in the refractive index.
authors.forename: D
authors.initials: D
authors.lastname: Bogunovic
authors.forename: S G
authors.initials: SG
authors.lastname: Raymond
authors.forename: S
authors.initials: S
authors.lastname: Janssens
authors.forename: D
authors.initials: D
authors.lastname: Clarke
authors.forename: O
authors.initials: O
authors.lastname: Bodley
authors.forename: S
authors.initials: S
authors.lastname: Ashforth
authors.forename: M C
authors.initials: MC
authors.lastname: Simpson
authors.forename: J W
authors.initials: JW
authors.lastname: Quilty