Titanium dioxide-based Q-switched dual wavelength in the 1 micron region

Abstract

In this work a passively Q-switched dual-wavelength ytterbium-doped fiber laser using a titanium dioxide-based saturable absorber is proposed and proven. The system also utilizes a side-polished fiber in a ring cavity configuration to obtain the desired pulse train. A stable dual-wavelength pulse output is obtained at 1034.7 and 1039.0 nm, with a maximum pulse energy of 2.0 nJ, and a shortest pulse width of 3.2 μs. The generated pulse train is stable, and has a pulse repetition rate from 31.2 to 64.5 kHz.

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

“…The stability of other three kinds of fundamental frequency pulses were similarly tested, and similar phenomena were observed. The mode-locked pulses could not exist if the SA was removed from the laser cavity and only Table 1 demonstrated the parameters of dual-wavelength (or multi-wavelength) passively Q-switched and mode-locked fiber lasers based on various 2D materials SAs, such as graphene [32], [45], SWNTs (single-walled carbon nanotubes) [33], [44], TMO (transition metal oxide) [34]- [36], BP (black phosphorus) [37], LMDCs [28], [38], [40] and TI (topological insulator) [39], [41]- [43], etc. Obviously, compared with other 2D materials SAs, there were narrow pulse width, high slope efficiency and low threshold in our experimental results.…”

Titanium Dioxide Langmuir–Blodgett Film Saturable Absorber for Passively Q-switched Nd:GdVO4 Laser

“…The TiO 2 -nanomaterial SAs previously reported exhibit excellent nonlinear optical absorption properties with modulation depths of 30-40% at a laser wavelength of 1.5 μm [27]- [31]. However, high optical absorption caused by such large modulation depths results in too much intracavity loss in a solid-state laser cavity, hindering laser generation.…”

“…In fact, many investigations on the third-order nonlinear optical properties of TiO 2 films such as third-harmonic generation [40], [41] and four-wave mixing [42] have been conducted. Since 2016, in consideration of its several-picosecond recovery time [24], nonlinear optical characteristics [23], [25], and wide absorption band extending to the near-infrared region [26], attempts have been made to utilize TiO 2 in 1-, 1.5-, and 2-μm all-fiber pulsed lasers as SAs [27]- [31]. In these lasers, TiO 2 nanomaterials are embedded within a polymer film like polyvinyl alcohol (PVA) film and sandwiched in between two end-face ferrules of FC fiber connectors.…”

Dual-wavelength Bi2Se3-based passively Q-switching Nd3+-doped glass all-fiber laser

“…Compared to actively QS fiber lasers, passively QS fiber lasers possess the attractive advantages of compactness, simplicity, and flexibility. With the assistance of the saturable absorbers (SAs), passively QS pulses can be generated in fiber lasers [5][6][7][8] . Moreover, allfiber laser sources hold considerable research interest owing to their compact, convenient, and cost-effective designs.…”