Latching operation in a tunable wavelength filter using Si sampled grating waveguide with ferroelectric liquid...

Area of Science:

• Photonics
• Materials Science
• Optical Engineering

Background:

• Tunable wavelength filters are crucial components in optical communication and sensing systems.
• Existing filters often require continuous power for operation, limiting their efficiency and applicability.
• Ferro-electric liquid crystals (FLC) offer potential for low-power, bistable optical switching.

Purpose of the Study:

• To propose and demonstrate a novel tunable wavelength filter with a latching function.
• To investigate the performance of silicon sampled grating waveguides with FLC cladding.
• To achieve efficient and power-free wavelength tuning and switching.

Main Methods:

• Fabrication of a tunable wavelength filter using silicon-on-insulator (SOI) wafer with a sampled grating waveguide.
• Integration of ferro-electric liquid crystal (FLC) as cladding material.
• Characterization of the device's optical properties, including stop band width, wavelength shift, and switching behavior.

Main Results:

• The sampled grating waveguide exhibited narrower stop bands compared to uniform gratings.
• A thinner silicon core enhanced the wavelength shift due to increased FLC effect.
• Successful demonstration of bistable switching operation with latching capability, requiring no state-sustaining power.

Conclusions:

• The proposed tunable wavelength filter with FLC cladding is a promising solution for low-power optical devices.
• The device achieves efficient wavelength tuning and power-free latching, suitable for advanced photonic applications.
• Further research can explore optimization for broader applications in optical networks and signal processing.