High-efficiency 10 J diode pumped cryogenic gas cooled Yb:YAG multislab amplifier

Area of Science:

• Laser Physics
• Solid-State Lasers
• Cryogenic Engineering

Background:

• Diode-pumped solid-state lasers (DPSSLs) are crucial for high-power applications.
• Cryogenic cooling enhances laser performance by reducing thermal effects.
• Yb:YAG is a promising gain medium due to its favorable spectroscopic properties.

Purpose of the Study:

• To demonstrate the first diode-pumped, gas-cooled, cryogenic multislab Yb:YAG amplifier.
• To characterize its performance across a range of cryogenic temperatures.
• To evaluate its potential for high-energy pulsed laser generation.

Main Methods:

• Utilized a multislab Yb:YAG architecture.
• Employed diode pumping for efficient energy deposition.
• Implemented gas cooling to achieve cryogenic temperatures (88-175 K).
• Configured four-pass and three-pass extraction geometries for nanosecond pulse amplification.

Main Results:

• Achieved a maximum small-signal single-pass gain of 11.0 at 88 K.
• Delivered 10.1 J at 1 Hz (four-pass) and 6.4 J at 10 Hz (three-pass).
• Recorded optical-to-optical conversion efficiencies of 21% and 16%, respectively.
• Demonstrated the highest pulse energy from a cryo-cooled Yb-laser to date.
• Achieved the highest efficiency for a multijoule diode-pumped solid-state laser system.

Conclusions:

• The diode-pumped, gas-cooled, cryogenic multislab Yb:YAG amplifier is a highly effective system.
• Cryogenic operation significantly boosts laser performance, enabling record-breaking energy and efficiency.
• This technology paves the way for next-generation high-energy laser systems.