Compact, highly efficient ytterbium doped bismuthate glass waveguide laser.

Area of Science:

• Materials Science
• Optics and Photonics
• Laser Physics

Background:

• Bismuthate glasses offer unique optical properties for laser applications.
• Ytterbium (Yb) doping is crucial for developing efficient near-infrared lasers.
• Ultrafast laser inscription enables precise fabrication of optical waveguides.

Purpose of the Study:

• To achieve high laser slope efficiencies in ytterbium-doped bismuthate glass waveguides.
• To investigate the impact of ultrafast laser inscription on waveguide performance.
• To correlate laser performance with propagation losses and optical properties.

Main Methods:

• Fabrication of buried channel waveguides using ultrafast laser inscription in ytterbium-doped bismuthate glass.
• Characterization of laser slope efficiency, measuring values exceeding 78%.
• Assessment of propagation losses and fluorescence properties of ytterbium ions within the waveguide.

Main Results:

• Laser slope efficiencies close to the quantum defect limit were achieved.
• Efficiencies in excess of 78% were demonstrated in the fabricated waveguides.
• Low propagation losses and preserved fluorescence properties of ytterbium ions were observed.

Conclusions:

• Ultrafast laser inscribed waveguides in ytterbium-doped bismuthate glass can achieve outstanding laser performance.
• The combination of low propagation losses and preserved ion fluorescence is key to high efficiencies.
• This demonstrates a promising approach for developing advanced fiber and waveguide lasers.