High-efficiency solar-pumped laser with a grooved Nd:YAG rod

Area of Science:

• Optics and Photonics
• Renewable Energy Technologies
• Laser Physics

Background:

• Solar-pumped lasers offer a sustainable alternative for laser power generation.
• Improving the efficiency and beam quality of solar laser systems is crucial for practical applications.
• The geometry of the laser gain medium significantly impacts optical performance.

Purpose of the Study:

• To evaluate the performance of a Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) laser rod with a grooved sidewall in solar-pumped laser systems.
• To compare the efficiency and beam quality of the grooved rod against an unpolished rod.
• To investigate the impact of enhanced solar energy concentration on laser output.

Main Methods:

• Two solar-pumped laser setups were utilized, each employing a Fresnel lens (1.03 m²) as the primary solar concentrator.
• The first setup incorporated a ceramic conical cavity as the secondary concentrator.
• The second setup added a water tube lens within a copper conical cavity for increased solar energy concentration.

Main Results:

• The first setup yielded a maximum output power of 20.3 W with a slope efficiency of 8.34% (laser power vs. focused solar power).
• The second setup, with enhanced concentration, produced 27 W of output power and a slope efficiency of 9%.
• In both configurations, the grooved Nd:YAG rod demonstrated superior efficiency and beam quality compared to an unpolished rod.

Conclusions:

• A grooved sidewall design enhances the performance of Nd:YAG rods in solar-pumped laser applications.
• The grooved rod design leads to improved laser output power and efficiency.
• Further optimization of solar energy concentration, combined with the grooved rod, promises higher laser performance.