Nl. Taranenko et al., 3-WAVE ENVELOPE SOLITONS - POSSIBILITY OF CONTROLLING THE SPEED OF LIGHT IN FIBER, Journal of lightwave technology, 12(7), 1994, pp. 1101-1111
Theory predicts that three-wave envelope solitons (TWES) can be genera
ted in dual-mode optical fibers by simultaneous injection of two copro
pagating optical modes. The mechanism of the three-wave interaction is
the recently observed intermodal forward stimulated Brillouin scatter
ing (FSBS). The dynamics of soliton generation depends on the duration
of the injected pulses, the pump power, and the attenuation time cons
tant. For the adiabatic modulation of injected optical waves, a new ty
pe of generation has been analyzed: an acoustical wave structure that
scatters the incident pump into the Stokes wave is formed in the fiber
prior to and after the soliton generation. This structure appears as
a result of FSBS and serves as a TWES ''launcher.'' We identify this t
ype of generation in earlier soliton experiments in stimulated Raman s
cattering. The TWES velocity depends on the pump power. For a typical
dual-mode fiber, the speed of TWES can be adjusted over four orders of
magnitude by adjusting the pump power between 0.01 and 200 mW. The du
ration of the soliton is < 3 ms due to the acoustic attenuation. The l
ength of the fiber can be shorter than the length of the soliton while
preserving the same TWES characteristics. Both Ar+ and Nd:YAG lasers
are suitable for TWES generation.