In this work, we introduce a four green-light wavelength splitter device, based on six slot-waveguide structures. Silica and gallium nitride materials were chosen for confining the green light inside the slot-waveguide area in a transverse magnetic field mode. The device functioned as a 1 × 4 demultiplexer, which demultiplexes wavelengths in the green-light band with wavelength range of 500–530 nm with an accurate spacing of 10 nm. The coupling between the six slot-waveguide units was analyzed using the classical mode theory and the full vectorial beam propagation method. Simulation results showed that the four wavelengths could be demultiplexed after a short coupling length of 106.5 μm with low losses around 0.108–0.127 dB, full width at half maximum around 8.99–9.39 nm, and excellent crosstalk around −21.13 to −24.1 dB. The device has the potential to increase data bitrate by utilizing the wavelength division multiplexing technique in visible light communication systems.

在这项工作中，我们介绍了一种基于六个缝隙波导结构的四个绿光波长分离器设备。选择二氧化硅和氮化镓材料以在横向磁场模式下将绿光限制在缝隙波导区域内。该设备用作1×4多路分解器，可对绿光波段中波长范围为500–530 nm的波长进行多路分解，精确间隔为10 nm。使用经典模式理论和全矢量波束传播方法分析了六个缝隙波导单元之间的耦合。仿真结果表明，在短的耦合长度106.5μm之后，四个波长可以解复用，损耗低至0.108-0.127 dB，半峰全宽约为8.99-9.39 nm，且串扰在-21.13至-24.1 dB附近。