Chirped optical pulses with time-bandwidth products of more than 7000
and energies of approximately 5 nJ have been produced in a diode-pumpe
d erbium-doped fiber laser. The large chirp was achieved using pulsed
active modelocking in a long cavity with net normal dispersion. The ex
perimental results were supported by numerical simulations used to mod
el the temporal dependence of the pulse intensity and chirp. (C) 1997
Elsevier Science B.V.