Passively Q-Switched Yb:CALGO Laser Based on Mo:BiVO₄ Absorber

Area of Science:

• Optics and Photonics
• Materials Science
• Laser Physics

Background:

• Passively Q-switched lasers are crucial for generating high-energy pulses.
• Developing efficient and stable saturable absorbers is key to advancing Q-switched laser performance.
• Molybdenum-doped bismuth vanadate (Mo:BiVO₄) is explored as a potential material for optical applications.

Purpose of the Study:

• To demonstrate a stable, passively Q-switched laser using a Mo:BiVO₄ saturable absorber.
• To characterize the nonlinear optical properties of Mo:BiVO₄ for laser applications.
• To evaluate the performance of the Yb:CaGdAlO₄ laser system.

Main Methods:

• Fabrication and characterization of Mo:BiVO₄ nanoparticles using transmission electron microscopy, Raman spectroscopy, and linear absorption.
• Nonlinear transmission measurements of Mo:BiVO₄ using a pulsed laser (30 ps, 1064 nm, 10 Hz).
• Integration of Mo:BiVO₄ as a saturable absorber in a passively Q-switched Yb:CaGdAlO₄ laser.

Main Results:

• Characterization confirmed the structure and morphology of the Mo:BiVO₄ nanoparticles.
• The passively Q-switched laser achieved a maximum output power of 510 mW.
• The laser operated at a repetition rate of 87 kHz with a pulse width of 3.18 μs, yielding a single pulse energy of 5.8 μJ and a peak power of 1.84 W.

Conclusions:

• Mo:BiVO₄-based saturable absorbers are effective for passively Q-switched lasers.
• The demonstrated laser system exhibits stable performance in the near-infrared region.
• Mo:BiVO₄ is a promising candidate for saturable absorbers in near-infrared laser applications.