Cascaded telecom fiber enabled high-order random fiber laser beyond zero-dispersion wavelength

Abstract

Four-wave mixing induced spectral broadening near the zero-dispersion wavelength (ZDW) of the fiber is a bottleneck factor that limits the further wavelength extending in cascaded random fiber lasers (RFLs). In this Letter, we successfully suppress the spectral broadening near the ZDW of the fiber in the cascaded RFL by simply combining two kinds of commercial telecom fibers with different ZDWs, G655C fiber with ZDW around 1.52 µm and G652D fiber with ZDW around 1.31 µm. As a result, an 8th order Stokes light component at 1721 nm with a maximum output power of 2.1 W and a spectral purity of 96.94% is realized in this telecom-fiber-based cascaded RFL. This work provides a reference of nonlinear effect management in fiber lasers as well as affords a cost-effective way with great potential of realizing high-power widely tunable fiber lasers.

Nonlinear effects-based 1.7 μm fiber lasers: A review and prospect

“…On the basis of the previous research, they used the filtered ASE light source as the pump source, which was amplified by erbium-doped fiber amplifier for optical power, as shown in , successfully suppressing the spectral broadening near the fiber zero-dispersion wavelength (ZDW) in the cascaded RFL and obtaining a continuous wave Raman laser output at 1721 nm with a power of 2. 16 W, the result of which provides a significantly potential and cost-effective method to realizing high-power tunable fiber lasers [38]. In 2020, a high-power CW/pulsed 1.7 µm Raman fiber laser was reported by Grimes from Denmark [39].…”

Spectral Manipulations of Random Fiber Lasers: Principles, Characteristics, and Applications

“…[124] By employing two passive fibers with different zero-dispersion wavelengths, up to eighth-order cascaded RRFL with a wavelength of 1721 nm and spectral purity of 96.94% has been presented. [125] In addition, taking advantage of the Raman gain peaks of phosphosilicate fiber at both 13.2 and 39.9 THz, the Stokes light with a much longer wavelength can be stimulated by the pump with the same operating wavelength. [126][127][128][129][130] Meanwhile, based on the boson peak, a phosphosilicate fiber-based RRFL with a quantum defect of only 1.3% was demonstrated, which possesses the potential to be used for suppressing thermal-induced effects in RRFLs.…”

All-Fiber Tunable Pulsed 1.7 μm Fiber Lasers Based on Stimulated Raman Scattering of Hydrogen Molecules in Hollow-Core Fibers

“…However, the conversion efficiency of TDFs is relatively low due to strong reabsorption in the 1.7 μm band, while the preparation technology of BDFs and THDFs are not mature. The other is through nonlinear optical effects in solid-core fibers, including SRS [ 11 , 12 ], self-phase modulation [ 13 , 14 ], soliton self-frequency shift [ 15 , 16 ], and four-wave mixing [ 17 , 18 ], but the output laser linewidth is often wide. For some applications such as gas detection, narrow linewidth laser beams are needed to accurately distinguish the gas absorption lines, and a longer coherence length is also conducive to long-distance detection.…”