A dual-wavelength pumped low noise fiber laser includes a fiber laser (10)comprising a pair of Bragg gratings (14, 16) at oppositeends of a fiber laser cavity (18) which is co-doped with two rare-earthdopants, ER+3 Yb+3, so as to allow lasing to occur at a lasingwavelength .lambda.L. A first pump signal (20) efficiently pumps the Yb to theexcited state and the Yb energy is transitioned to the Er atomswhich ultimately lase at the desire lasing frequency. Because Yb is pumped soefficiently, high pump absorption is achieved, therebyproviding high laser output power and, consequently, reduced RIN.Simultaneously, a second pump signal (52) directly pumps the Er at adifferent wavelength .lambda.P2 which populates the lacing transition morequickly, thereby allowing sufficient bandwidth of a closed loop controlon the second pump signal (52) to control low frequency RIN spiking due torelaxation oscillations in the laser.
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