Compact and Efficient Thin-Film Lithium Niobate Modulators

Thin-film lithium niobate (TFLN) modulators have garnered significant attention in the field of integrated photonics due to their ability to manipulate light. Numerous TFLN modulators have been demonstrated over the past few years, with speed records consistently being broken. However, due to the low refractive index contrast and anisotropic properties of TFLN, modulators based on this material feature larger device sizes and lower efficiency. A more compact and efficient modulator is important, as it is required for future dense integration and low power consumption applications. There have been some reports on how to reduce device size, and research is ongoing. A comprehensive summary can help individuals understand the current state of research and existing problems. In this review, we provide an overview of recent advancements in TFLN modulator technology, focusing on compactness and efficiency. Herein, various types of modulators, such as the Mach-Zehnder interferometer, Michelson interferometer, resonator cavity, and Z-cut type modulators, are discussed. Moreover, potential improvement strategies and applications for compact and efficient TFLN modulators in advanced photonic systems are explored. In conclusion, in this review, the recent achievements in compact and efficient TFLN modulators are summarized and their significance in various optoelectronic applications is emphasized. Thin-film lithium niobate (TFLN) modulators are gaining attention in integrated photonics for their light manipulation capabilities. Despite speed advancements, TFLN modulators are less efficient due to low refractive index contrast, necessitating compactness and efficiency improvements for future integration and low power usage. In this review, recent TFLN modulator developments are outlined and enhancement strategies and applications in advanced photonic systems are explored.image (c) 2023 WILEY-VCH GmbH