Simulation and design of recycle carrier Mach-Zehnder modulator on thin film lithium niobate

With growing demand for high-speed, energy-efficient optical communication systems, there is a pressing need for modulators that combine low power consumption, broad bandwidth, and a compact footprint. Reducing the half-wave voltage (Vπ) is important for minimizing driving power and enabling compatibility with complementary metal-oxide-semiconductor (CMOS) electronics, while maintaining a wide electro-optic bandwidth is critical for high data-rate transmission. However, conventional thin-film lithium niobate (TFLN) Mach–Zehnder modulators face a trade-off between achieving low Vπ and high bandwidth. In this work, we present a recycle carrier modulator (RCM) on the TFLN platform that uses a high-Q microring resonator (MRR) structure to enhance modulation efficiency without significantly limiting speed.