High-power synchronously pumped AgGaS(2) optical parametric oscillator

Area of Science:

• Optics and Photonics
• Nonlinear Optics
• Laser Technology

Background:

• Optical parametric oscillators (OPOs) are crucial for generating tunable laser light.
• Efficiently extracting generated beams is key to maximizing OPO output power.
• Silver gallium sulfide (AgGaS2) is a promising nonlinear crystal for infrared generation.

Purpose of the Study:

• To achieve high average power generation in the infrared region using an AgGaS2 OPO.
• To investigate the impact of cavity design on OPO performance and beam extraction.
• To demonstrate tunable infrared output with high spatial quality.

Main Methods:

• A Q-switched, mode-locked laser was employed for synchronous pumping of the AgGaS2 OPO.
• The OPO cavity was initially configured as a standing-wave resonator.
• The cavity was subsequently redesigned into a ring configuration for improved beam extraction.

Main Results:

• Average infrared power exceeding 2 W was generated.
• Tunable output was achieved across the 1.4 to 1.9 µm wavelength range.
• A ring cavity design enabled efficient extraction of signal and idler beams, reaching 1.5 W and 620 mW respectively at 2 kHz.

Conclusions:

• The AgGaS2 OPO system is capable of generating significant average power in the infrared.
• A ring cavity configuration significantly enhances the extraction efficiency and spatial quality of the generated beams.
• This work advances high-power, tunable infrared light generation for scientific and technological applications.