Development of Wavelength Demultiplexers Based on a Binary Search Inverse Design Algorithm

This paper introduces a novel approach to the efficient design of wavelength demultiplexer using a different Direct Binary Search (DBS) technique. The enhanced DBS method introduces a new state, "2" representing small air columns on the silicon plate, in addition to the traditional "0" (silicon) and "1" (large air holes). In this context, we have developed a concise three-channel wavelength demultiplexer designed for efficient wavelength division multiplexing in the terahertz frequency range. Employing the enhanced DBS method has significantly augmented the inverse design process, providing greater design freedom and expanding the design space. This methodology has ultimately yielded a compact 3D wavelength demultiplexer with a smaller footprint and heightened transmission efficiency. Simultaneously, it plays a crucial role in enhancing the practical application performance across the entire terahertz communication system.