Bound solitons with 103-fs pulse width and 585.5-fs separation from Di-nolm figure-8 fiber laser

Ultra-short bound-soliton pulses with pulse 103-fs width and 585.5-fs separation are observed experimentally from a figure-8 passive mode-locked fiber laser incorporated with a dispersion-imbalanced nonlinear optical loop mirror (DI-NOLM). To our knowledge, these are the most closely bound solitons produced from fiber laser to date, and the bound-soliton separation and pulsewidth re remains unchanged even after 1.2-Km single-mode fiber (SMF) transmission. (C) 2003 Wile, Periodicals. Inc.