10W ASE-free single-mode high-power double-cladding Er³⁺-Yb³⁺amplifier

High-power high-repetition-rate single-mode Er-Yb-doped fiber laser system

“…According to specification of our spectrum analyzer the measurement level range is −85 to + 10 dBm, and taking into account our measurement setup, even ~1 µW level could be detectable. However, unlike previous reports [4], we did not observe any spurious ASE at 1 µm at this pump power in neither the forward nor the backward direction (as monitored through the 1030 port of the WDM). One of the most important parameters of an amplifier system is the level of output power variations.…”

“…Despite these difficulties, 297 W of CW power was achieved by using Er-Yb co-doped double-clad (DC) large mode area fiber [3]. In Ref [4], the authors demonstrated the possibility to reach about 10 W cw output power in single mode operation with a beam quality M 2~1 . In order to manage the nonlinear effects, which are strengthened by the anomalous dispersion of fibers at 1550 nm, one approach is to use large mode area (LMA) fibers, in spite of the difficulty to maintain high beam quality [5][6][7][8].…”

Yb band parasitic lasing suppression in Er/Yb-co-doped pulsed fiber amplifier based on all-solid photonic bandgap fiber

“…[3] two fiber Bragg gratings (FBG) and a specially designed wide-band filter were utilized to filter out the Yb-ASE, this solution being effective but at the same time-costly and time-consuming for tailor-made FBGs. Another approach was using the counter-propagating pumping scheme [4], but the Yb-ASE can still appear under high-power operation. Meanwhile, the standard tapered fiber bundle (TFB) couplers are not suitable for long-term operation for counter-pumping scheme because their low core-to-cladding isolation can lead to low damage threshold.…”

Pulsed dual-stage fiber MOPA source operating at 1550 nm with arbitrarily shaped output pulses

“…Erbium/ytterbium co-doped fibers make excellent active gain media to build medium/highpower sources in the 1.5-1.6 µm region. Constructions using Er/Yb-doped fibers providing single-frequency multiplewatt continuous-wave (CW) output were already shown in the literature [5][6][7]. In the pulsed regime, the extractable energy is strongly limited by nonlinear effects (especially stimulated Brillouin scattering, SBS) and unwanted amplified spontaneous emission (ASE) which lead to fast selfsaturation [8].…”