Yuancheng Cai, Lin Zhang, Jiao Zhang, Bingchang Hua, Kexin Ma, Junjie Ding, Xingwang Bian, Mingzheng Lei, Yingzhou Liu, Jiankang Li, Zhigang Xin, Xingyu Chen, Jun Cai, Pan Pan, Yongming Huang, Jinjun Feng, Min Zhu, Xiaohu You
Abstract Terahertz (THz) bands are critical for next-generation wireless fronthaul/backhaul applications. However, they face a fundamental coverage range limitation due to low emission power, severe path loss, and poor receiving sensitivity, especially in photonics-assisted THz systems beyond 300 GHz. To address this limitation, we develop a 335 GHz continuous-wave traveling wave tube amplifier with an output power close to 4 W and a gain of over 50 dB, and construct a novel yet simple diversity receiving scheme to improve the receiving signal-to-noise ratio by ~3 dB. Through hybrid photonic–electronic synergy, combining photonics-assisted THz generation, high-power THz amplification, and spatial diversity reception, a record-breaking kilometer-scale THz wireless communication at 335 GHz—a highly challenging atmospheric window—is demonstrated. We first achieve a net rate of 27.84 Gbit s −1 over a 2.2 km wireless link—yielding an unprecedented rate–distance product of 61,248 Gbit s −1 ∙ m—beyond 300 GHz to the best of our knowledge.