Heterogeneous silicon-on-lithium niobate electro-optic modulator for 100-Gbaud modulation

Abstract

Integrated lithium niobate (LN) electro-optic (EO) modulators are emerging for applications in next-generation optical fiber communication networks. To date, LN crystal waveguides have led the technology for high-speed modulators. On the other hand, on-chip LN modulators are expected to realize scalable signaling devices with mature complementary metal-oxide-semiconductor technology. In this study, a silicon-loaded LN modulator on the insulator substrate featuring a small footprint, a low driving voltage, and high-speed EO modulation is designed and fabricated. No etching or patterning of the LN is required. The measured halfwave-voltage length product is 1.9 V cm with a static modulation extinction ratio of 17.9 dB. The fabricated LN modulator has a modulation bandwidth of 60 GHz and supports high-speed signaling at a data rate up to 200 Gbit/s.