title: Formation and propagation of coupled ultraslow optical soliton pairs in a cold three-state double- system.
abstract: We investigate the simultaneous formation and propagation of coupled ultraslow optical soliton pairs in a cold, lifetime-broadened three-state double-Lambda atomic system. Starting from the equations of motion of atomic response and two-mode probe-control electromagnetic fields, we derive coupled nonlinear Schrödinger equations that govern the nonlinear evolution of the envelopes of the probe fields in this four-wave mixing scheme by means of the standard method of multiple scales. We demonstrate that for weak probe fields and with suitable operation conditions, a pair of coupled optical solitons moving with remarkably slow propagating velocity can be established in such a highly resonant atomic medium. The key elements to such a shape preserving, well matched yet interacting soliton pair is the balance between dispersion effect and self- and cross-phase modulation effects of the system.
authors.affiliation: Department of Physics, East China Normal University, Shanghai, China. gxhuang@phy.ecnu.edu.cn
authors.forename: Guoxiang
authors.initials: G
authors.lastname: Huang
authors.forename: Kaijun
authors.initials: K
authors.lastname: Jiang
authors.forename: M G
authors.initials: MG
authors.lastname: Payne
authors.forename: L
authors.initials: L
authors.lastname: Deng