On-chip metamaterial-enabled high-order mode-division multiplexing
Yu He, Xingfeng Li, Yong Zhang, Shaohua An, Hongwei Wang, Zhen Wang, Haoshuo Chen, Yetian Huang, Hanzi Huang, Nicolas K. Fontaine, Roland Ryf, Yuhan Du, Lu Sun, Xingchen Ji, Xuhan Guo, Yingxiong Song, Qianwu Zhang, Yikai Su
Abstract
Mode-division multiplexing (MDM) technology enables high-bandwidth data transmission using orthogonal waveguide modes to construct parallel data streams. However, few demonstrations have been realized for generating and supporting high-order modes, mainly due to the intrinsic large material group-velocity dispersion (GVD), which make it challenging to selectively couple different-order spatial modes. We show the feasibility of on-chip GVD engineering by introducing a gradient-index metamaterial structure, which enables a robust and fully scalable MDM process. We demonstrate a record-high-order MDM device that supports TE0–TE15 modes simultaneously. 40-GBaud 16-ary quadrature amplitude modulation signals encoded on 16 mode channels contribute to a 2.162 Tbit / s net data rate, which is the highest data rate ever reported for an on-chip single-wavelength transmission. Our method can effectively expand the number of channels provided by MDM technology and promote the emerging research fields with great demand for parallelism, such as high-capacity optical interconnects, high-dimensional quantum communications, and large-scale neural networks.