Bandwidth and wavelength tunable optical passband filter based on silicon multiple microring resonators.

Area of Science:

• Photonics
• Optical Engineering
• Materials Science

Background:

• Bandpass filters are crucial components in optical communication systems.
• Achieving wide bandwidth tunability in compact filters remains a significant challenge.

Purpose of the Study:

• To propose and experimentally demonstrate an ultra-compact silicon bandpass filter.
• To achieve wide bandwidth tunability while maintaining a good shape factor.

Main Methods:

• Utilized a cascaded structure of multiple micro-ring resonators.
• Controlled resonant frequencies of microring resonators to tune bandwidth.
• Experimentally validated filter performance, including bandwidth, shape factor, free spectral range, and center wavelength tunability.

Main Results:

• Demonstrated a wide bandwidth tunability from 75 to 300 GHz.
• Achieved a good shape factor ranging from 0.24 to 0.44.
• Obtained a wide free spectral range of approximately 1.2 THz.
• Showcased linear tuning of the center wavelength over several nanometers.
• Achieved an ultra-compact footprint of only 0.053 mm².

Conclusions:

• The proposed micro-ring resonator-based silicon bandpass filter offers significant advantages in terms of size and tunability.
• This technology holds promise for next-generation optical communication and signal processing applications.