title: Ultrawidely tunable single-mode fiber acousto-optic filter.
abstract: A single-mode fiber (SMF) acousto-optic tunable filter (AOTF) with a tuning range of more than 300 nm is demonstrated. The SMF used in the experiment has a ring of symmetric holes within the cladding, which causes a larger mode-index difference between the first and the second higher-order antisymmetric modes than those of a conventional SMF. As a result, the difference in beatlengths between the core mode and the higher-order modes is highly increased, which makes it possible for the SMF AOTF to exhibit a single resonance peak in the transmission spectrum over the wavelength range of 1.3-1.6 μm for given acoustic frequencies of 3.1-3.8 MHz.
authors.affiliation: Photonics Research Center, Korea Institute of Science and Technology, Seoul 136-791, Korea. sdlim@kist.re.kr
authors.forename: Sun Do
authors.initials: SD
authors.lastname: Lim
authors.forename: Kyung Jun
authors.initials: KJ
authors.lastname: Park
authors.forename: Sunghoon
authors.initials: S
authors.lastname: Eom
authors.forename: Je-Myung
authors.initials: JM
authors.lastname: Jeong
authors.forename: Byoung Yoon
authors.initials: BY
authors.lastname: Kim
authors.forename: Sang Bae
authors.initials: SB
authors.lastname: Lee