UV-pumped visible Tb³⁺-lasers.

Area of Science:

• Solid-state laser physics
• Materials science
• Quantum electronics

Background:

• Terbium-doped materials are promising for laser applications.
• UV pumping offers advantages over visible light pumping for certain laser media.

Purpose of the Study:

• To investigate continuous-wave laser operation of Tb3+:LiLuF4 under UV pumping.
• To evaluate the efficiency and performance characteristics of this laser system.
• To explore the potential for high-power diode-pumped lasers.

Main Methods:

• Continuous-wave laser operation was demonstrated using a frequency-doubled Ti:sapphire laser at 359 nm.
• The crystal used was terbium-doped lithium lutetium fluoride (Tb3+:LiLuF4).
• Absorption cross sections and population dynamics were analyzed.

Main Results:

• Efficient population of the upper laser level (5D4) was observed due to cross-relaxation.
• Laser operation was achieved in the green and yellow spectral regions.
• Slope efficiencies of 41% (green) and 20% (yellow) were recorded.
• Optical-to-optical efficiencies were twice as high compared to cyan-blue pumping.

Conclusions:

• UV pumping of Tb3+:LiLuF4 is a viable method for efficient laser operation.
• The material's properties are suitable for developing future high-power diode-pumped lasers.
• Higher absorption cross sections in the UV enable shorter gain media, beneficial for high-power applications.