Dual-Wavelength Passively Mode-Locked Yb-Doped Fiber Laser Based on a SnSe₂-PVA Saturable Absorber

Abstract

In this letter, tin diselenide (SnSe 2) was successfully prepared with the liquidphase exfoliation method and embedded into polyvinyl alcohol as a saturable absorber (SA) in a dual-wavelength passively mode-locked Yb-doped fiber laser. Stable mode-locked pulses with a maximum average output power of 2.55 mW and a slope efficiency of 1.3% at the fundamental repetition rate of 333 kHz were achieved. By properly adjusting polarization state, four kinds of dual-wavelength fundamental frequency mode-locked pulses with peak wavelength intervals of 0.4, 1.0, 1.5, and 1.9 nm were obtained, and the corresponding waveforms with different single-pulse shapes were investigated in our work. A maximum signal-to-noise ratio of 71.04 dB indicates that SnSe 2 is promising to serve as a SA in passively mode-locked fiber lasers.

High-Peak-Power Sub-Nanosecond Mode-Locking Pulses Generated by a Dual-Loss-Modulated QML Laser with AOM and SnSe2

“…The atomic force microscopy (AFM) showed the morphology and thickness of SnSe 2 film in Figure 1c,d; the corresponding average thickness of the SnSe 2 film sample was about ~5.9 nm. Assuming that the monolayer flake thickness was 0.6 nm, the saturable absorber we made had about 9-10 layers [25]. The SnSe 2 flake sample also had a large lateral dimension of about ~2 µm.…”

“…Then, in 2019, a SnSe 2 -based solid-state passive Q-switched laser at 1.3 and 1.9 µm was reported, which demonstrate the effective optical modulation properties of the SnSe 2 [23]. For fiber lasers, the pulse characteristics modulated by the SnSe 2 -SA were also successfully demonstrated by Q-switched or mode-locked technologies [24][25][26][27]. However, in solid-state lasers, studies on the mode-locking pulse modulation characteristics of SnSe 2 are not enough.…”

Crack Resistance and Toughening Mechanism of Nano-SiO2 Reinforced PVA Fiber Cement-based Composites in Steel Bridge Engineering

“…The location of the crack is related to the size of the material defect. The crack at the beginning will be generated at the largest initial defect, the crack is affected by the size of the defect, and then new cracks are gradually generated from high to low, so that the crack will eventually form a crack [21].…”

Multi-pulse dynamic patterns in a mode-locked erbium-doped fiber laser based on an Sb2S3-PVA saturable absorber

“…Recently, LMSs as a novel 2D material, including SnS 2 [28], TiS 2 [29], SnSe 2 [18,30], TiSe 2 [31], In 2 Se 3 [32], Sb 2 S 3 [33,34], etc, were found to possess many outstanding optical and photonic properties, such as a broad band response wavelength range of linear optical absorption, an ultrafast relaxation time and recovery time, a large modulation depth, a high damage threshold, Pauli blocking-induced saturable absorption, strong saturation intensity and high optical nonlinearity, so they have been widely used as SAs in fiber and solid-state lasers. Antimony sulfide (Sb 2 S 3 ), as a novel LMS, with an orthorhombic structure consisting of ribbon-like chains of parallel molecular (Sb 4 S 6 ) n [35], possesses outstanding physical and optical properties, including exotic photoconductive effect, high Seebeck coefficient, high absorption coefficient, etc [36,37].…”