Silicon photonic arrayed waveguide grating with 64 channels for the 2 µm spectral range

Area of Science:

• Photonics
• Optical Communications
• Materials Science

Background:

• The demand for higher bandwidth in optical fiber communications necessitates exploring wavelengths beyond the conventional C+L bands.
• The 2 µm spectral region is identified as a promising candidate for next-generation optical communication systems.
• Development of high-performance photonic devices is crucial for realizing advanced optical functionalities.

Purpose of the Study:

• To report the fabrication and characterization of an integrated silicon photonic arrayed waveguide grating (AWG) for the 2 µm waveband.
• To demonstrate the potential of silicon photonics for dense wavelength division multiplexing (DWDM) in this emerging spectral region.

Main Methods:

• Fabrication of a 64-channel AWG using a commercial silicon photonic foundry.
• Characterization of the AWG's spectral performance, including channel spacing and bandwidth.
• Implementation of a TiN metal layer for thermal tuning and measurement of tuning efficiency.
• Assessment of the device's footprint and on-chip insertion loss.

Main Results:

• The fabricated AWG operates with 64 channels spaced at approximately 50 GHz (0.7 nm), covering 1967 nm to 2012 nm.
• An on-chip insertion loss of approximately 5 dB was measured.
• Thermal tuning efficiency of 0.27 GHz/mW was achieved using a TiN metal layer.
• The device exhibits a compact footprint of 2.3 mm × 2 mm.

Conclusions:

• The demonstrated silicon photonic AWG is a viable component for DWDM in the 2 µm spectral band.
• The compact size and thermal tunability offer advantages for integration into future optical communication systems.
• This work contributes to extending the capacity of optical fiber communications by utilizing under-explored wavelength bands.