title: Deep-notch, ultracompact long-period grating in a large-mode-area photonic crystal fiber.
abstract: An extremely short long-period grating (LPG) with strong resonance has been developed in a large-mode-area photonic crystal fiber (PCF) by use of the heat source of a CO2 laser. We believe that such a LPG in pure silica PCF is the first example to be obtained with the point-by-point technique. The fabrication method is simple and repeatable. The resulting LPG has 8 periods, written by a CO2 laser, within a 2.8-mm length of fiber, which yields a deep notch of core-cladding mode coupling of -31.5 dB at the telecommunication wavelength of 1529.2 nm, with a FWHM of approximately 0.7 nm. The principal advantages of this LPG are that it is practical, cost effective, and compact.
authors.affiliation: Network Technology Research Center, Nanyang Technological University, 50 Nanyang Drive, Research TechnoPlaza, Singapore 637553. eynzhu@ntu.edu.sg
authors.forename: Yinian
authors.initials: Y
authors.lastname: Zhu
authors.forename: Ping
authors.initials: P
authors.lastname: Shum
authors.forename: Joo-Hin
authors.initials: JH
authors.lastname: Chong
authors.forename: M K
authors.initials: MK
authors.lastname: Rao
authors.forename: Chao
authors.initials: C
authors.lastname: Lu