title: Tilted Bragg gratings in step-index polymer optical fiber.
abstract: We report the first slightly tilted Bragg gratings photo-inscription in polymer optical fiber (POF). For this, we make use of trans-4-stilbenemethanol-doped photosensitive step-index poly(methyl methacrylate) (PMMA) POFs. Tilted fiber Bragg gratings (TFBGs) are inscribed in the near-infrared wavelength range using the scanning phase mask technique with a tilted phase mask in the plane perpendicular to the laser beam direction. The transmitted amplitude spectrum evolution of a 3° TFBG is analyzed as a function of the surrounding refractive index. A maximum sensitivity close to 13  nm/RIU (refractive index unit) is obtained in the range 1.42-1.49.
authors.forename: Xuehao
authors.initials: X
authors.lastname: Hu
authors.forename: Chi-Fung Jeff
authors.initials: CF
authors.lastname: Pun
authors.forename: Hwa-Yaw
authors.initials: HY
authors.lastname: Tam
authors.forename: Patrice
authors.initials: P
authors.lastname: Mégret
authors.forename: Christophe
authors.initials: C
authors.lastname: Caucheteur