Reconfigurable and tunable compact comb filter and (de)interleaver on silicon platform.

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Semiconductor Devices

Background:

• Wavelength-division multiplexing (WDM) systems require efficient optical filters and (de)interleavers.
• Existing devices often lack reconfigurability and fine-tuning capabilities.
• Silicon photonics offers a scalable platform for integrated optical devices.

Purpose of the Study:

• To propose and demonstrate a novel reconfigurable and tunable chip-scale comb filter and (de)interleaver on a silicon platform.
• To integrate Sagnac loop mirrors (SLMs) with multi-mode interference (MMI) assisted tunable Mach-Zehnder interferometer (MZI) couplers.
• To achieve switchable comb filtering and (de)interleaving functionalities with independent control over extinction ratio and wavelength.

Main Methods:

• Fabrication of a silicon-based photonic integrated device utilizing SLMs and MMI-assisted tunable MZI couplers.
• Implementation of a Fabry-Perot (FP) cavity within the device structure.
• Utilizing thermo-optic tuning via micro-heaters for reconfigurable and tunable operations.

Main Results:

• Demonstration of switchable operation between comb filter and (de)interleaver modes.
• Achieved wavelength tunability for both comb filter (~0.0224 nm/mW) and (de)interleaver (~0.0193 nm/mW) with demonstrated central wavelength shifts.
• Characterized comb filter with a 3-dB bandwidth of ~0.032 nm and (de)interleaver with passband bandwidths of ~0.225 nm (3-dB) and ~0.326 nm (20-dB).

Conclusions:

• The developed silicon photonic device successfully integrates reconfigurable comb filtering and (de)interleaving functions.
• The device exhibits excellent tunability in both wavelength and extinction ratio.
• This technology holds significant potential for robust and advanced WDM optical communication systems.