Affiliation:
1. Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan Hubei 430074 China
2. 2012 Labs Huawei Technologies Co., Ltd Wuhan Hubei 430079 China
Abstract
AbstractThin‐film lithium niobate (TFLN)‐based electro‐optic modulators have extensive applications in broadband optical communications due to their broad bandwidth, high extinction ratio, and low optical loss. However, compared with their silicon and indium‐phosphide (InP)‐based counterparts, TFLN exhibits lower modulation efficiency. Simultaneously achieving low driving voltage and a wide modulating bandwidth poses a significant challenge. To address this limitation, this paper proposes a transparent conductive oxide film into the device, resulting in an ultra‐high modulation efficiency of 1.02 V cm. The fabricated composite electrode not only attains high modulation efficiency but also sustains a high electro‐optic bandwidth, as evidenced by the 3 dB roll‐off at 108 GHz and the transmission of PAM‐4 signals at 224 Gbit s−1. The fabricated device offers novel solutions for low‐cost, high‐performance modulators, thereby facilitating the downsizing of TFLN‐based multichannel optical transmitter chips.
Funder
National Key Research and Development Program of China
Natural Science Foundation of Hubei Province
National Natural Science Foundation of China