  We present a high-speed wavelength tunable photonic crystal fiber-based
source capable of generating tunable femtosecond solitons in the infrared
region. Through measurements and numerical simulation, we show that both the
pulsewidth and the spectral width of the output pulses remain nearly constant
over the entire tuning range from 860 to 1160 nm. This remarkable behavior is
observed even when pump pulses are heavily chirped (7400 fs^2), which allows to
avoid bulky compensation optics, or the use of another fiber, for dispersion
compensation usually required by the tuning device.
