Electro-Optically Switchable Optical True Delay Lines of Meter-Scale Lengths Fabricated on Lithium Niobate on Insulator Using Photolithography Assisted Chemo-Mechanical Etching
Jun-xia Zhou1,2, Ren-hong Gao3,4, Jintian Lin3,5*, Min Wang1,2, Wei Chu1,2, Wen-bo Li3,4, Di-feng Yin3,4, Li Deng1,2, Zhi-wei Fang1,2, Jian-hao Zhang3,4, Rong-bo Wu3,4and Ya Cheng1,2,3,4,5,6,7*
1State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China 2XXL—The Extreme Optoelectromechanics Laboratory, School of Physics and Electronics Science, East China Normal University, Shanghai 200241, China 3State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China 4University of Chinese Academy of Sciences, Beijing 100049, China 5Collaborate CAS Center for Excellence in Ultra-intense Laser Science, Shanghai 201800, China 6Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China 7Shanghai Research Center for Quantum Sciences, Shanghai 201315, China
Abstract：Optical true delay lines (OTDLs) of low propagation losses, small footprints and high tuning speeds and efficiencies are of critical importance for various photonic applications. Here, we report fabrication of electro-optically switchable OTDLs on lithium niobate on insulator using photolithography assisted chemo-mechanical etching. Our device consists of several low-loss optical waveguides of different lengths which are consecutively connected by electro-optical switches to generate different amounts of time delay. The fabricated OTLDs show an ultra-low propagation loss of $\sim 0.03$ dB/cm for waveguide lengths well above 100 cm.
2020, Vol. 37 
