High-Performance Thin Film Lithium Niobate Electro-Optic Modulator By Embedding Structure

Electro-optic modulators with low driving voltage and wide bandwidth are critical for advanced analog and digital communication systems. Improving the modulation efficiency of thin-film lithium niobate (TFLN) modulators is essential to reducing drive voltage and device length, thereby enabling compact chip integration and enhanced modulation bandwidth. This work introduces a novel TFLN modulator featuring an embedded dual capacitance-loaded traveling-wave electrode (EDC-TWE) to achieve superior electro-optic modulation efficiency and minimized optical loss. The fabricated modulator, with a 10-mm-long modulation region, achieves a half-wave voltage of 1.45 V and an electro-optic modulation bandwidth exceeding 40 GHz, demonstrating its potential for high-performance optical communication applications.