Folded Heterogeneous Silicon and Lithium Niobate Mach–Zehnder Modulators with Low Drive Voltage
, Mengyue Xu, Mingbo He, Shengqian Gao, Xian Zhang, Lidan Zhou, Lin Liu, Siyuan Yu and Xinlun Cai *
Carlos A Rios Ocampo
Round 1
Reviewer 1 Report
Sun et al. report the fabrication and characterization of a folded heterogeneous lithium niobate on silicon optical modulator. They demonstrate driving voltages as low as 1.24 Vπ with 40GHz bandwidth in a folded 21mm waveguide for a total of 9mm device, which is impressive. Their design using crossings to overcome the electric field flip after a U-turn is clever, scalable and, to the best of my knowledge, novel in this type of modulators. The paper is well written, and the supplementary information is relevant and clarifies several points. I recommend publication of this paper as it is, there isn’t much I can comment on or suggest besides maybe adding information on the losses due to the metal pads on top of the silicon waveguides (what’s the gap?). Otherwise, this is an excellent paper.
Author Response
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Author Response.docx
Reviewer 2 Report
Any critical comments. Good and clearly written paper.
Author Response
Thank you for your time and effort in reviewing our work.
