Efficient visible laser operation of Tb:LiYF₄ and LiTbF₄

Area of Science:

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

Background:

• Terbium-activated materials are promising for visible light lasers.
• Previous research has explored various Tb³⁺-doped crystals for laser applications.

Purpose of the Study:

• To investigate laser performance of Tb³⁺-activated LiYF₄ and LiTbF₄ crystals.
• To achieve efficient laser operation in the yellow and green spectral regions.
• To explore novel gain media for high-energy pulsed lasers.

Main Methods:

• Fabrication and characterization of Tb:LiYF₄ and LiTbF₄ crystals.
• Diode-pumped laser experiments in continuous-wave (CW) and pulsed modes.
• Spectroscopic analysis and performance evaluation (slope efficiency, output power).

Main Results:

• Record-high slope efficiency of 63% for Tb³⁺-lasers achieved with c-cut 15%Tb:LiYF₄ at 544 nm.
• Maximum output power of 1.17 W obtained at 544 nm.
• First-time successful laser operation of LiTbF₄ demonstrated, with a slope efficiency of 45% at 544 nm.
• Yellow laser operation (582 nm) in σ-polarization achieved with 21% slope efficiency.

Conclusions:

• Tb:LiYF₄ offers excellent performance for green laser generation.
• LiTbF₄ is a promising new gain medium for high-energy pulsed lasers due to its high active-ion concentration and long lifetime.
• These findings advance the development of efficient visible solid-state lasers.