Topological Berry Antenna on a Silicon Chip for Terahertz Wireless Communication

Nonzero Berry curvature is central to the existence of topological edge states in electronic and photonic valley‐Hall systems. While manipulating the Berry curvature in condensed matter systems is challenging, valley‐Hall topological photonics offer unprecedented control, where the broken spatial inversion symmetry alters the Berry curvature. Herein, an all‐silicon Berry antenna is presented, using a continuously varying geometry corresponding to a gradual change in Berry curvature. The on‐chip topological edge mode with a tunable field extent is achieved to enhance effective antenna aperture, creating a high‐gain on‐chip photonic antenna with perfectly planar wavefronts. Experimentally, a maximum gain of 17 dBi that supports 20 Gbps chip‐to‐chip wireless communication is demonstrated, with active optical tunability of the antenna gain with modulation depths of 8 dBi. This Berry antenna paves the way for the development of complementary metal‐oxide‐semiconductor (CMOS) compatible topological Berry devices, with potential applications in integrated micro‐/nano‐photonics, next‐generation wireless communications (6G to Xth generation), and terahertz detection and ranging.