Open AccessLow Vπ thin-film lithium niobate modulator fabricated with photolithography
Author(s) -
Ye Liu,
Heng Li,
Jia Liu,
Su Tan,
Qiaoyin Lu,
Weihua Guo
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.414250
Subject(s) - lithium niobate , photolithography , materials science , optical modulator , optics , electro optic modulator , optoelectronics , fabrication , modulation (music) , bandwidth (computing) , voltage , electrode , thin film , phase modulation , electrical engineering , telecommunications , computer science , physics , nanotechnology , medicine , alternative medicine , pathology , quantum mechanics , phase noise , acoustics , engineering
Thin-film lithium niobate (TFLN) modulators are expected to be an ideal solution to achieve a super-wide modulation bandwidth needed by the next-generation optical communication system. To improve the performance, especially to reduce the driving voltage, we have carried out a detailed design of the TFLN push-pull modulator by calculating 2D maps of the optical losses and V π for different ridge waveguide depths and electrode gaps. Afterwards the modulator with travelling wave electrodes was fabricated through i-line photolithography and then characterized. The measured V π for a modulator with 5-mm modulation arm length is 3.5 V, corresponding to voltage-length product of 1.75 V·cm, which is the lowest among similar modulators as far as we know. And the measured electro-optic response has a 3-dB bandwidth beyond 40 GHz, which is the limitation of our measurement capability. The detailed design, fabrication and measurement results are presented.