Stable Q-switched Fiber Laser Research Articles

Self-induced Q-switched fiber laser using tantalum aluminum carbide as a passive modulator

A self-induced Q-switched erbium-doped fiber laser operating at 1563 nm was achieved by integrating a passive modulator based on tantalum aluminum carbide (Ta2AlC) MAX phase film embedded into polyynyl alcohol. The modulator, serving as a saturable absorber (SA), established a modulation depth of 9% and a saturation intensity of 0.3 MW cm−2. Upon integration of the film SA, a stable Q-switched fiber laser was obtained, generating pulses with a minimum width of 7.6 µs at a repetition rate of 45.1 kHz, within a pump power range of 24.9–59.7 mW. The corresponding maximum average output power, maximum pulse energy, and highest peak power were determined at 1.6 mW, 36.2 nJ, and 4.7 mW, respectively. The RF fundamental spectrum exhibited a good signal-to-noise ratio of 61 dB, indicating excellent pulse signal quality. This demonstration of Ta2AlC MAX phase film Q-switched laser may open promising possibilities for scientific applications such as material processing.

Microparticle optical trapping of silica gel by Au-NP Q-switched fiber laser pulses

This study demonstrates a method for microparticle optical trapping of silica gel using a stable Q-switched fiber laser (QFL) pulse. Gold nanoparticle (Au-NP) were fabricated as saturable absorbers on a side-polished optical fiber (SPF) to achieve stable QFL pulses of frequencies 25.81 kHz. Silica gel microparticles with a radius of 300–400 µm produced a dissimilar attractive trapping force based on the viscous drag exerted on the light field of the QFL. Shifts were observed at wavelengths of 1533.8–1541.0 nm and frequencies of 25.81–28.87 kHz. The validity of the numerical model is proven and the proposed model can be applied to examine the behavior of surface plasmon polaritons (SPP) modes in microparticle optical trapping. These findings confirm that the proposed system facilitates absorption microparticle trapping at the 1540 nm wavelength region.

Output energy enhancement in a dual-wavelength Q-switched fiber laser based on a ternary MoWSe2 saturable absorber

• The optical modulation property of ternary transition metal sulfide-MoWSe 2 was investigated. • Stable Q-switched fiber laser with the maximum single pulse energy and peak power of 151.4 nJ and 98.91 W was obtained using MoWSe 2 as a saturable absorber. • Dual-wavelength output was achieved with the pump power increased from the Q-switched laser threshold to the maximum. As a novel ternary selenide-based transition metal dichalcogenide (TMD), few-layered molybdenum tungsten selenide (MoWSe 2 ) was fabricated using liquid phase exfoliation method and applied in a Q-switched fiber laser as a saturable absorber. Dual-wavelength operation was achieved with the increase of pumping strength. The shortest pulse width and the maximum repetition rate were monitored to be 1.53 μs and 85.71 kHz, corresponding to a maximum single pulse energy and peak power of 151.4 nJ and 98.91 mW, respectively. The results indicate ternary MoWSe 2 could be a promising candidate in Q-switched laser applications.

Q-switched all-fiber laser based on titanium trisulfide

Titanium trisulfide (TiS3) is one of the members of the transition metal dichalcogenides. Due to the optical properties of the material, we explore its applications in nonlinear optics. In this paper, we prepare TiS3 saturable absorber (SA) by the chemical vapor transmission-mechanical exfoliation method-wet transfer. The modulation depth of TiS3-SA is measured to be 39.03 %. Using this SA, we obtain a relatively stable Q-switched fiber laser with the pulse duration of 506.5 ns and a signal-to-noise ratio of 50 dB. Because the TiS3-based Q-switched erbium-doped fiber laser has the characteristics of high modulation depth and stability, TiS3 as a nonlinear optical material has potential in the field of ultrafast photonics.

Stable and Efficient Pulsed Mid-Infrared Laser Generation from an Er3+-Doped ZBLAN Fiber Laser

We demonstrate a stable and efficient passively Q-switched 2.8 μm Er3+-doped ZBLAN fiber laser with a broadband semiconductor saturable absorber mirror. Enabled by the broadband optical modulator, the stable Q-switched fiber laser can deliver a maximum average power over 700 mW with corresponding per-pulse energy of 8.19 μJ and a pulse width of 1.3 μs at a repetition rate of 88.6 kHz under an incident pump power of 3.8 W. In addition, the slope efficiency can reach 22.5%. To the best of our knowledge, this is the highest reported slope efficiency for the passively Q-switched Er3+-doped ZBLAN fiber laser.