39  W narrow spectral linewidth monolithic ytterbium-doped fiber MOPA system operating at 976  nm

Abstract

We report on a monolithic narrow spectral linewidth master oscillator power amplifier (MOPA) delivering up to 39 W around 976 nm with very high contrast. The amplifier is based on an ytterbium-doped large mode area (LMA) octagonal double clad (DC) active fiber with parameters optimized for long living three-level operation.

Review of High-Power Continuous Wave Yb-Doped Fiber Lasers near 980 nm

“…With the DCYF, a 5.5 W fiber laser near 980 nm was demonstrated with a slope efficiency of 25% [43]. In 2020, a DCYF with a 35 µm core and 125 µm inner cladding was presented [44]. In this fiber, the core NA was about 0.07, and the confined Yb-doped core was used for the single-mode operation (the diameter of the Yb-doped region was about 20 µm, see Figure 7b).…”

Theoretical and experimental investigation of Al3+ ion-suppressed phase-separation structures in rare-earth-doped high-phosphorus silica glasses

“…to increase the solubility of RE ions, which improves the gain efficiency. [7][8][9][10] However, with the rapid development of high-power fiber lasers, it has become difficult for low-concentration co-doped silica-based glasses to meet the requirements of high-power operation. [11][12][13][14] In recent years, RE-doped silica-based composite glasses (Re-SCGs) have attracted considerable attention due to their high gain efficiencies, tunable crystal-field environments, and unique thermodynamic properties.…”

“…to increase the solubility of RE ions, which improves the gain efficiency. 7–10 However, with the rapid development of high-power fiber lasers, it has become difficult for low-concentration co-doped silica-based glasses to meet the requirements of high-power operation. 11–14…”

An Ytterbium-Doped Narrow-Bandwidth Randomly Distributed Feedback Laser Emitting at a Wavelength of 976 nm

“…For this reason, specially designed active fibers are used to achieve an acceptably high pumpto-signal conversion efficiency. In particular, this goal can be achieved by introducing excessive optical losses into the spectral region of 1030 nm [12,13], or by creating fibers with an increased ratio of the area of the core to the cross-section area of the first reflective cladding [14][15][16][17][18].…”