Chip-scale 290-GHz photonic wireless communication via coherent power combining

This Letter demonstrates an on-chip 290-GHz photonic wireless transmitter that co-integrates InGaAs/InP uni-traveling-carrier photodiodes (UTC-PDs), a microstrip Y-branch power combiner, and a 2 × 2 patch array antenna on a silicon carbide (SiC) substrate. Benefiting from the high thermal conductivity of SiC, the platform enables robust high-photocurrent excitation, and each UTC-PD reaches a 10 mA saturation photocurrent at a -0.6 V bias. The co-integrated 2 × 2 patch array provides an estimated directivity of 10.5 dBi while maintaining ∼55^∘ 3-dB beamwidths in both the E- and H-planes. To scale the radiated output, coherent power combining is implemented with the microstrip Y-branch network, and optical phase control enables a peak effective isotropic radiated power of 12.8 dBm. Wireless link experiments at 290 GHz validate chip-level operation, achieving up to 10 Gbit/s with bit-error rates below the 7% HD-FEC threshold and further demonstrating real-time uncompressed 4 K video streaming. Together, these results establish a chip-integrated photonic THz transmitter on a SiC platform that supports high-rate wireless communication.