Tuning the delay time of harmonically mode-locked erbium-doped fiber laserpulses by a frequency-discriminated phase shifter

A delay-time tunable, actively mode-locked erbium-doped fiber rising laser is demonstrated by using a voltage-controlled phase-locked phase shifter as an inherent timing module. By changing the voltage from -3.35 to 3.6 V, th e maximum tuning range of the phase and the delay time of the optical pulse train repeated at 500 MHz from the laser can be up to 340 degrees (similar to1.9 pi) and 1.9 ns (nearly one period), respectively, under a tuning res ponsivity of 0.27 ps/mV. (C) 2001 John Wiley & Sons, Inc.