1200  nm pumped Tm³⁺:Lu₂O₃ ceramic lasers

Area of Science:

• Laser Physics
• Materials Science
• Solid-State Lasers

Background:

• Thulium-doped lasers are crucial for various applications, but their excitation efficiency can be limited.
• Optimizing pump sources and wavelengths is key to enhancing laser performance.

Purpose of the Study:

• To experimentally demonstrate and characterize a 1200-nm pumped Thulium (Tm³⁺):Lutetium oxide (Lu₂O₃) ceramic laser.
• To investigate the impact of 1200-nm pumping on energy efficiency and operational characteristics.

Main Methods:

• Utilized a tunable Cr⁴⁺:forsterite laser for gain-switched pumping near 1200 nm.
• Measured the excitation spectrum and determined optimal pump bands.
• Compared energy efficiency with 800-nm pumping.
• Observed transitions in output wavelength and pulse characteristics at higher pump energies.

Main Results:

• Identified optimal pumping bands centered around 1198 nm, 1204 nm, and 1211 nm.
• Achieved a highest slope efficiency of 21.5% at 1204 nm.
• Demonstrated a ~40% improvement in slope efficiency using 1200-nm pumping versus 800-nm pumping.
• Observed a transition to dual-wavelength operation (2066 nm and 1967 nm) and characterized temporal pulse behavior.

Conclusions:

• 1200-nm pumping provides significantly improved energy efficiency for Tm³⁺:Lu₂O₃ ceramic lasers.
• This alternative excitation scheme offers a promising pathway for developing high-performance Tm³⁺:Lu₂O₃ ceramic lasers.