Nelan, SeanMercante, AndrewHurley, CooperShi, ShouyuanYao, PengShopp, BenjaminPrather, Dennis W.2022-04-062022-04-062022-03-04Sean Nelan, Andrew Mercante, Cooper Hurley, Shouyuan Shi, Peng Yao, Benjamin Shopp, and Dennis W. Prather, "Compact thin film lithium niobate folded intensity modulator using a waveguide crossing," Opt. Express 30, 9193-9207 (2022)1094-4087https://udspace.udel.edu/handle/19716/30758Copyright 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement. This article was originally published in Optics Express. The version of record is available at: https://doi.org/10.1364/OE.453050.A small footprint, low voltage and wide bandwidth electro-optic modulator is critical for applications ranging from optical communications to analog photonic links, and the integration of thin-film lithium niobate with photonic integrated circuit (PIC) compatible materials remains paramount. Here, a hybrid silicon nitride and lithium niobate folded electro-optic Mach Zehnder modulator (MZM) which incorporates a waveguide crossing and 3 dB multimode interference (MMI) couplers for splitting and combining light is reported. This modulator has an effective interaction region length of 10 mm and shows a DC half wave voltage of roughly 4.0 V, or a modulation efficiency (Vπ ·L) of roughly 4 V·cm. Furthermore, the device demonstrates a power extinction ratio of roughly 23 dB and shows .08 dB/GHz optical sideband power roll-off with index matching fluid up to 110 GHz, with a 3-dB bandwidth of 37.5 GHz.en-USArticle