High-repetition-rate single-frequency Ho:YAG MOPA system.

Area of Science:

• Laser Physics
• Solid-State Lasers
• Quantum Optics

Background:

• Single-frequency lasers are crucial for applications requiring high spectral purity.
• Developing high-energy, single-frequency lasers at longer wavelengths (2.09 μm) presents unique challenges.
• Master Oscillator and Power Amplifier (MOPA) architectures offer a pathway to high-energy, single-frequency output.

Purpose of the Study:

• To demonstrate a stable, single-frequency Ho:YAG Master Oscillator and Power Amplifier (MOPA) system operating at 2.09 μm.
• To characterize the output energy, pulse width, and spectral properties of the developed MOPA system.
• To assess the spectral quality relative to the Fourier transform limit.

Main Methods:

• Utilizing a continuous-wave Ho:YAG non-planar ring oscillator as the seed laser.
• Implementing a Ho:YAG MOPA architecture for power amplification.
• Employing the heterodyne technique to measure the spectral half-width of the output pulse.

Main Results:

• A stable, single-frequency Ho:YAG MOPA system was successfully demonstrated at a 1.25 kHz pulse repetition frequency.
• The system achieved a maximum output energy of 13.76 mJ with a pulse width of 178.9 ns.
• The measured spectral half-width was 2.65 MHz, approximately 1.06 times the Fourier transform limit.

Conclusions:

• The developed Ho:YAG MOPA system provides a robust platform for generating high-energy, single-frequency laser pulses at 2.09 μm.
• The spectral performance indicates excellent beam quality and potential for applications demanding narrow linewidths.
• This work contributes to the advancement of high-power, single-frequency solid-state laser technology.