Large-bandwidth, high-sensitivity, and large dynamic range electric field sensors are gradually replacing their traditional counterparts. The lithium-niobate-on-insulator (LNOI) material has emerged as an ideal platform for developing such devices, owing to its low optical loss, high electro-optical modulation efficiency, and significant bandwidth potential. In this paper, we propose and demonstrate an electric field sensor based on LNOI. The sensor consists of an asymmetric Mach–Zehnder interferometer (MZI) and a tapered dipole antenna array. The measured fiber-to-fiber loss is less than -6.7 dB, while the MZI structure exhibits an extinction ratio of greater than 20 dB. Moreover, 64-QAM signals at 2 GHz were measured, showing an error vector magnitude (EVM) of less than 8%.
Tingan Li, Zhao Liu, An Pan, Chenglin Shang, Yong Liu, Cheng Zeng, Jinsong Xia, "QAM signal with electric field sensor based on thin-film lithium niobate [Invited]," Chin. Opt. Lett. 21, 120041 (2023)
