Nd:YVO4 amplifier for ultrafast low-power lasers

Area of Science:

• Laser physics and nonlinear optics
• Materials science for laser gain media
• Ultrafast optics and photonics

Background:

• High-power amplification of ultrafast laser pulses is crucial for various scientific and industrial applications.
• Nd:YVO4 (neodymium-doped yttrium orthovanadate) lasers are known for their good thermal properties and efficient operation.
• Existing high-power laser systems often face limitations in pulse duration or repetition rate.

Purpose of the Study:

• To design and demonstrate an efficient, diffraction-limited Nd:YVO4 amplifier for ultrafast pulses.
• To investigate the amplifier's performance with different low-power ultrafast seed lasers.
• To achieve high output power with short pulse durations from the Nd:YVO4 amplifier.

Main Methods:

• Development of a two-module Nd:YVO4 amplifier end-pumped at 808 nm with 30 W absorbed power.
• Amplification experiments using three different seeders: a 50 mW, 7 ps Nd:YVO4 oscillator, a 2 mW, 15 ps Yb fiber laser, and a 30 mW, 300 fs Nd:glass laser.
• Characterization of output power, pulse duration, and beam quality.

Main Results:

• Achieved up to 9.5 W output power with 8 ps pulses from a 250 MHz vanadate seeder.
• Amplified a 20 MHz fiber laser seeder to 6 W output power.
• Extracted Fourier-limited 4 ps pulses at 7 W output power using the femtosecond Nd:glass seeder.
• Demonstrated record short pulses (<4 ps) for Nd:YVO4 lasers at output powers >= 7 W.

Conclusions:

• The developed Nd:YVO4 amplifier enables efficient, high-power amplification of ultrafast pulses.
• The system demonstrates a novel approach to leverage the gain bandwidth of vanadate amplifiers for high output power and short pulses.
• This technology offers a promising alternative to thin disk oscillators and regenerative amplifiers for specific ultrafast applications.