A hybrid AlGaInAs-silicon evanescent waveguide photodetector

Area of Science:

• Photonics
• Optoelectronics
• Materials Science

Background:

• Silicon photonics offers a scalable platform for integrated optical circuits.
• Efficient light detection is crucial for optical communication and sensing systems.
• Hybrid integration approaches are needed to combine dissimilar materials for advanced functionalities.

Purpose of the Study:

• To demonstrate a hybrid waveguide photodetector with AlGaInAs quantum wells bonded to a silicon waveguide.
• To characterize the performance of the photodetector in terms of responsivity and quantum efficiency.
• To explore the potential integration of this photodetector with other silicon photonic components.

Main Methods:

• Fabrication of a hybrid waveguide structure by bonding AlGaInAs quantum wells to a silicon waveguide.
• Optical characterization of the photodetector under reverse bias.
• Measurement of fiber-coupled responsivity and internal quantum efficiency at 1.5 µm wavelength.

Main Results:

• The hybrid waveguide photodetector demonstrated efficient light absorption in the AlGaInAs quantum wells.
• Achieved a fiber-coupled responsivity of 0.31 A/W.
• Obtained an internal quantum efficiency of 90% at a 1.5 µm wavelength.

Conclusions:

• The developed hybrid waveguide photodetector shows promising performance for integrated silicon photonics.
• This device can be integrated with silicon evanescent lasers for power monitoring.
• Potential for integration with silicon evanescent amplifiers for preamplified receivers.