研究目的
Designing a directional coupler type polarization beam splitter using silicon waveguides for 1550–1600 nm wavelengths, utilizing the coupling strength difference between the TE and TM modes and a reversed Δβ structure to achieve a wide operational wavelength range.
研究成果
The designed directional coupler type polarization beam splitter using silicon waveguides with a reversed Δβ structure achieves a wide operational wavelength range of over 100 nm with a 20 dB extinction ratio at 1520–1620 nm wavelengths. The fabrication width tolerance exceeds 10 nm, making it suitable for foundry processes. This simple structure offers a significant advantage for wavelength division multiplexing systems.
研究不足
The design requires a wide gap between waveguides to attain a sufficient extinction ratio for the TE mode, which could limit the compactness of the device. The fabrication width tolerance, while sufficient for foundry processes, may still pose challenges for very precise applications.
