Cryogenically cooled 946nm Nd:YAG laser.

Area of Science:

• Laser physics
• Solid-state materials
• Spectroscopy

Background:

• Neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers are crucial for various applications.
• Operating at 946 nm on the (4)F(3/2) → (4)I(9/2) transition presents unique challenges.
• Cryogenic cooling can enhance laser performance by modifying spectroscopic properties.

Purpose of the Study:

• To demonstrate the first multi-Watt output power from a diode-pumped, cryogenically cooled Nd:YAG laser at 946 nm.
• To characterize the temperature-dependent spectroscopic properties of the Nd:YAG gain medium.
• To investigate the potential benefits of cryogenic temperatures for laser operation.

Main Methods:

• Utilized a diode-pumped laser system with a cryogenically cooled Nd:YAG crystal.
• Operated the laser at the 946 nm transition under continuous wave (CW) conditions.
• Performed spectroscopic measurements of absorption and emission cross-sections from 77 K to 300 K.

Main Results:

• Achieved 3.8 W of CW output power with 12.8 W of absorbed pump power.
• Recorded a slope efficiency of 47% for the laser.
• Observed a ~2.5-fold increase in both absorption and emission cross-sections at 77 K compared to 300 K.

Conclusions:

• The study successfully demonstrated a high-power, cryogenically cooled Nd:YAG laser at 946 nm.
• Cryogenic temperatures significantly enhance the spectroscopic properties of Nd:YAG, leading to improved laser performance.
• This work paves the way for more efficient and powerful solid-state lasers operating at this wavelength.