title: Control of hollow-core photonic bandgap fiber ellipticity by induced lateral tension.
abstract: We describe the fabrication of elliptical hollow-core photonic bandgap fibers (EC-PBGFs). It was shown that the aspect ratio of the hollow core can be controlled by tuning the negative pressure in the space between the intermediate preform cane and outer jacketing tube, and by placing this preform assembly off-center in the furnace, resulting in lateral tension during the final draw. Modal birefringences of fabricated PBGFs with different aspect ratio were measured using a Sagnac loop interferometer. For the elliptical hollow core PBGF with aspect ratio of 2.34, the modal birefringence was measured to be about 4.6x10(-2) at 1,550 nm.
authors.affiliation: Photonics Research Team, Korea Institute of Science Technology (KIST), Seoul, Republic of Korea.
authors.forename: Gilhwan
authors.initials: G
authors.lastname: Kim
authors.forename: Taiyong
authors.initials: T
authors.lastname: Cho
authors.forename: Kyujin
authors.initials: K
authors.lastname: Hwang
authors.forename: Kwanil
authors.initials: K
authors.lastname: Lee
authors.forename: Kyung S
authors.initials: KS
authors.lastname: Lee
authors.forename: Sang Bae
authors.initials: SB
authors.lastname: Lee