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Researchers have proposed diverse techniques for fabricating saturable absorbers, including aqueous acid exfoliation, evanescent coupling, and electrochemical exfoliation, with fabrication complexity and limitations that reduce saturable absorber performance and application range. We describe mechanical exfoliation and transfer as an efficient and straightforward mechanism for a MAX phase nanomaterial, V2ZnC, expelled into a 48.926 µm thin saturable absorber film for passively Q-switched and mode-locked all-fibre lasers, exhibiting a modulation depth of 13.16%, non-saturable absorption to be 10.21%, and saturation intensity of 4.32 kW/cm2 MAX-SA; all of which demonstrated its superiority with a self-starting laser. The output laser was stable with a pulse width of 7.160 µs and a repetition rate of up to 62.23 kHz at a threshold pump power of 59.53 mW in Q-switched conditions and 346.8 ns pulse width with 963.3 kHz repetition rate at a pump power of 80.41 mW in mode-locked conditions. It is a excellent saturable absorber for the use of pulse laser production in all-fibre laser cavities because of its simple manufacturing process and outstanding optical, physical, thermal, and mechanical qualities. [ABSTRACT FROM AUTHOR]

Gold–titanium oxide nanocomposites (Au–TiO2 NCPs) were fabricated through pulsed laser-induced photolysis (PIPS) and verified to be usable for the visible light catalytic degradation of methylene blue (MB). The PIPS method can produce a sufficient amount of NCPs quickly and has potential to be commercialized. In contrast to other studies, we clarified the optical spectrum of the light sources, including peak power, bandwidth, and total intensity used for photodegradation reactions and discovered that the photodegradation efficiency of the produced Au–TiO2 NCPs in the wavelength range of 405 nm could reach 37% in 30 min due to the charge transfer between Au and TiO2. The control experiment shows that the addition of individual Au and TiO2 nanoparticles (NPs) to an MB solution has no enhancement of degradation ability under visible light illumination. The photodegradation of Au–TiO2 NCPs can be further improved by increasing the concentrations of auric acid and TiO2 NPs in a precursor under PIPS fabrication. [ABSTRACT FROM AUTHOR]