title: Modulational instability and parametric amplification induced by loss dispersion in optical fibers.
abstract: We show that modulational instability may arise even in the normal group-velocity dispersion regime of an optical fiber when the fiber loss (gain) varies depending on the wavelength. A simple analytical expression for the instability gain is obtained, which reveals that the odd-order terms of the loss dispersion are responsible for this phenomenon. The instability gain is measured experimentally in an optical-parametric-amplification configuration. Large parametric gain is induced in a non-phase-matched regime as we apply narrow band loss at the idler wavelength.
authors.affiliation: Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-Ku, Tokyo 153-8904, Japan. tanemura@ginjo.rcast.u-tokyo.ac.jp
authors.forename: Takuo
authors.initials: T
authors.lastname: Tanemura
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Ozeki
authors.forename: Kazuro
authors.initials: K
authors.lastname: Kikuchi