Rose gold nanoparticles film for generating Q-switched and mode-locked pulses

Abstract

Passively Q-switched and mode-locked Erbium doped fiber lasers have been successfully realized by using rose gold nanoparticles, which were embedded into polyvinyl alcohol as saturable absorber. The stable Q-switched laser was obtained at 1565.21 nm wavelength operation when a tiny piece of the prepared rose gold film was sandwiched between two fiber ferrules and incorporated into the proposed laser cavity. Q-switched pulses were obtained within a pump power range from 141.33 to 190.61 mW. At the maximum pump power, the laser operated at repetition rate of 84.75 kHz and pulse width of 4.16 µs while producing the highest single pulse energy of 12.81 nJ. By incorporating an additional 200 m long single-mode fiber into the laser cavity, stable mode-locked pulses were generated. It operated at repetition rate of 0.97 MHz, pulse width of 2.25 ps, maximum pulse energy of 3.12 nJ and a signal-to-noise ratio (SNR) of 63.81 dB.

Keywords

• Rose gold nanoparticles
• Passive saturable absorber
• Q-switching
• Mode-locking