Highly efficient, low-threshold monolithic distributed-Bragg-reflector channel waveguide laser in Al2O3:Yb3+.

Area of Science:

• Integrated photonics
• Laser technology
• Materials science

Background:

• Distributed Bragg reflector (DBR) lasers offer compact and efficient light sources.
• Ytterbium-doped materials are promising for visible and near-infrared lasers.
• Channel waveguides enable miniaturization and integration of photonic devices.

Purpose of the Study:

• To fabricate and characterize a monolithic DBR channel waveguide laser.
• To investigate the performance of ytterbium-doped aluminum oxide in a waveguide laser.
• To achieve efficient, single-mode, and single-polarization laser operation.

Main Methods:

• Fabrication of a 1 cm long monolithic DBR channel waveguide laser on a silicon substrate.
• Optical pumping of the ytterbium-doped aluminum oxide device using a 976 nm laser diode.
• Characterization of the laser's output spectrum, polarization, and power.

Main Results:

• Single-longitudinal-mode and single-polarization operation was achieved.
• The laser operated at a wavelength of 1021.2 nm.
• A maximum continuous-wave output power of 47 mW was obtained.
• A low launched pump power threshold of 10 mW was measured.
• A high slope efficiency of 67% was demonstrated.

Conclusions:

• The developed ytterbium-doped aluminum oxide waveguide laser is highly efficient.
• The monolithic DBR design enables compact and stable laser operation.
• This technology holds potential for various integrated photonic applications.