Ultra-narrow-linewidth, single-frequency distributed feedback waveguide laser in Al2O3:Er3+ on silicon

Area of Science:

• Photonics and Laser Technology
• Materials Science
• Integrated Optics

Background:

• Development of compact and efficient lasers is crucial for telecommunications and sensing.
• Erbium-doped materials are essential for achieving laser emission at telecommunication wavelengths.
• Silicon photonics offers a scalable platform for integrated optical devices.

Purpose of the Study:

• To realize and characterize a distributed feedback channel waveguide laser.
• To investigate the performance of erbium-doped aluminum oxide on a silicon substrate.
• To achieve single-longitudinal-mode and single-polarization operation.

Main Methods:

• Fabrication of a distributed feedback channel waveguide laser using erbium-doped aluminum oxide.
• Characterization of the laser's performance under diode-pumped continuous-wave operation.
• Measurement of threshold power, output power, slope efficiency, and emission linewidth.

Main Results:

• The laser demonstrated a low threshold of 2.2 mW absorbed pump power.
• Maximum output power exceeded 3 mW with a slope efficiency of 41.3%.
• Single-longitudinal-mode and single-polarization operation was achieved with a narrow linewidth of 1.70 kHz and a high Q factor of 1.14 x 10^11 at 1545.2 nm.

Conclusions:

• The successful realization of this device demonstrates the potential of erbium-doped aluminum oxide on silicon for integrated photonics.
• The achieved performance metrics, including high efficiency and narrow linewidth, are promising for various optical applications.
• This work contributes to the advancement of on-chip laser sources for future optical systems.