Designing Dispersion- and Mode-Area-Decreasing Holey Fibers for Soliton Compression. M.L.V.Tse, P.Horak, F.Poletti, and D.J.Richardson Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom. Email: [email protected]
Designing Dispersion- and Mode-Area-Decreasing Holey Fibers for Soliton Compression
M.L.V.Tse, P.Horak, F.Poletti, and D.J.Richardson
Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, United Kingdom. Email: [email protected]
Dispersion, Dispersion Slope and Effective Area Contour maps:
Compression of soliton pulses propagating in optical fibers with decreasing dispersion is a well-established technique . Using holey fibers it is possible to decrease dispersion (D) and effective mode area (Aeff) simultaneously, which potentially offers a greater range of variation in soliton compression factors. Moreover, soliton compression in new wavelength ranges below 1.3 mm can be achieved in holey fibers. Recently, this has been successfully demonstrated with femtosecond pulses at 1.06 mm .
Here, we investigate numerically the adiabatic compression of solitons at 1.55 mm in holey fibers which exhibit simultaneously decreasing in D and Aeff. We identify some of the limitations and propose solutions by carefully selecting paths in contour maps of D and Aeff in the (d/L, L) grid. Compression factors >10 are achieved for optimum fiber parameters.
Example: Path 2
What is a Holey Fiber?
Contour map for adiabatic compression factors versus pitch L and d/L for holey fibers of hexagonal geometry at 1.55 mm wavelength. (Normalized to the top left corner of the map, which has the largest value of D*Aeff) (green dotted line represents the single mode ‘SM’ and multi-mode ‘MM’ boundary)
Contour map for dispersion (ps/nm/km), dispersion slope (ps/nm2/km) and effective area (mm2) versus pitch L and d/L for holey fibers of hexagonal geometry at 1.55 mm wavelength.
Conventional Optical Fiber:
Input pulse: 400 fs
Simulated spectrum, no Raman effect.
Simulated spectrum, Ds= 0.
Soliton Compression Theory:
We have investigated adiabatic compression of femtosecond solitons in silica holey fibers of decreasing dispersion and effective mode area. These parameters are directly related to the structural design parameters L and d/L. A compression factor of 12 has been obtained for low-loss fibers in the adiabatic regime. A method for minimizing the fiber length required for adiabatic compression in the presence of propagation losses is suggested.
 S. V. Chernikov, E. M. Dianov, D. J. Richardson and D. N. Payne, “Soliton pulse compression in dispersion-decreasing fiber,” Opt. Lett. 18, 476 (1993).
 M. L. V. Tse, P. Horak, J. H. V. Price, F. Poletti, F. He, and D. J. Richardson, “Pulse compression at 1.06 mm in dispersion-decreasing holey fibers,” Opt. Lett. 31, 3504 (2006).
Long optical pulses
Nonlinear tapered holey fiber