A family of low-loss high-concentration rare-earth-doped Ga-As-Sb-S chalcogenide glass fibers for mid-infrared laser application

Area of Science:

• Materials Science
• Optoelectronics
• Laser Physics

Background:

• Mid-infrared fiber lasers are crucial for various applications, including spectroscopy and free-space communications.
• Developing efficient and stable gain media is essential for advancing mid-infrared laser technology.

Purpose of the Study:

• To introduce a novel chalcogenide glass composition (Ga0.8As34.2Sb5S60) as a gain medium for mid-infrared fiber lasers.
• To investigate the thermal stability, absorption, and emission properties of rare-earth-doped glasses.
• To fabricate and characterize few-mode double-clad fibers for high-performance laser applications.

Main Methods:

• Synthesis and characterization of a novel Ga-As-Sb-S chalcogenide glass.
• Doping the glass with rare-earth ions (Tm3+, Ho3+, Dy3+, Pr3+).
• Fabrication of few-mode double-clad fibers.
• Measurement of optical losses, thermal stability, and mid-infrared emission properties.

Main Results:

• The novel Ga0.8As34.2Sb5S60 glass demonstrated excellent thermal stability.
• Record-low optical losses were achieved in Ho3+-doped (0.31 dB/m) and Pr3+-doped (0.57 dB/m) fibers.
• High rare-earth solubility up to 2000 ppmw was observed.
• Dy3+- and Tm3+-doped fibers exhibited low losses (approx. 1-2 dB/m).

Conclusions:

• The developed chalcogenide glass is a promising gain medium for mid-infrared fiber lasers.
• The fabricated fibers possess properties suitable for high-performance lasers operating in the 2-5 µm range.
• This work contributes to the advancement of mid-infrared laser technology through novel material development.