title: Group velocity manipulation in active fibers using mutually modulated cross-gain modulation: from ultraslow to superluminal propagation.
abstract: We propose and experimentally demonstrate the propagation of slow/fast light in an erbium-doped fiber (EDF) using mutually modulated cross-gain modulation. The group velocity of the light signal can be manipulated by the effect of gain cross-saturation modulation by a saturating light at an arbitrary wavelength in the gain bandwidth of the EDF. The ultraslow propagation with a small group velocity of 5.6 × 10⁻³c (c is the light speed in free space) and superluminal propagation with a negative group velocity of -1.1 × 10⁻³c has been observed under different modulation phases.
authors.affiliation: Department of Physics, Key Laboratory for Laser Plasmas (Ministry of Education), State Key Lab of Advanced Optical Communication Systems and Networks, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: K
authors.initials: K
authors.lastname: Qian
authors.forename: L
authors.initials: L
authors.lastname: Zhan
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.forename: Z Q
authors.initials: ZQ
authors.lastname: Zhu
authors.forename: J S
authors.initials: JS
authors.lastname: Peng
authors.forename: Z C
authors.initials: ZC
authors.lastname: Gu
authors.forename: X
authors.initials: X
authors.lastname: Hu
authors.forename: S Y
authors.initials: SY
authors.lastname: Luo
authors.forename: Y X
authors.initials: YX
authors.lastname: Xia