Silicon-based wavelength division multiplexer using asymmetric grating-assisted couplers.

Area of Science:

• Photonics and Optical Engineering
• Telecommunications Technology

Background:

• Wavelength division multiplexing (WDM) is crucial for increasing fiber optic communication capacity.
• Asymmetric grating-assisted couplers offer potential for compact and efficient WDM devices.

Purpose of the Study:

• To propose and experimentally validate a novel WDM device utilizing asymmetric grating-assisted couplers.
• To demonstrate flexible bandwidth adjustment and effective sidelobe suppression.

Main Methods:

• Design and simulation of asymmetric grating-assisted couplers with varying corrugation widths.
• Experimental fabrication and characterization of the proposed WDM device.
• Analysis of insertion loss and sidelobe suppression ratio.

Main Results:

• Flexible adjustment of device bandwidth by altering grating corrugation width.
• Significant sidelobe suppression achieved with unilateral and bilateral amplitude apodization techniques.
• Low insertion loss (0.23dB–0.58dB) and high sidelobe suppression ratio (>10dB) demonstrated experimentally.

Conclusions:

• The proposed asymmetric grating-assisted coupler WDM is feasible and offers tunable bandwidth.
• Apodization techniques effectively reduce sidelobes, enhancing device performance and reducing channel crosstalk.