On‐Chip Polarization‐ and Frequency‐Division Demultiplexing for Multidimensional Terahertz Communication

Abstract Integrated terahertz (THz) technology is of great significance for driving high‐speed communication, sensing, and imaging with its advantages of miniaturization, low cost, and high efficiency. Recent research has focused on highly‐efficient transmitters and ultrafast detectors, as well as exploring new devices for coupling, transmission, and polarization control. However, multidimensional on‐chip multiplexing and demultiplexing techniques in the THz region still remains unexplored, due to the lack of multifunctional integrated components and systems. Here, a novel silicon‐based integrated multidimensional THz (de)multiplexer for high‐capacity communication is proposed and demonstrated based on ring resonators and polarization beam splitter‐rotators, which simultaneously enable the manipulation of THz polarization and frequency. Furthermore, a THz communication system operating in the 380 GHz band is experimentally demonstrated. By using on‐chip polarization‐ and frequency‐division multiplexing techniques, an aggregate data rate of 8 Gbit s −1 is successfully achieved with quadrature phase‐shift keying modulation scheme. This work provides a spectrally efficient way for accelerating the development of on‐chip THz technologies and the application in future large‐volume communications.