Advances in Bias Drift Mechanisms and Suppression Techniques for Thin‐Film Lithium Niobate Electro‐Optic Modulators

ABSTRACT Thin‐film lithium niobate electro‐optic modulators are key components in high‐speed photonic systems, yet bias drift severely limits their long‐term stability and reliability. This review systematically examines the physical origins of bias drift—ion migration, thermal effects, structural factors, and stress effects—across multiple timescales. Current suppression strategies are critically evaluated, from material/structural optimization (surface passivation, annealing, cladding doping) to bias control techniques (dither‐based feedback, model‐driven compensation), highlighting their respective trade‐offs in performance, complexity, and cost. Architecture‐specific considerations for Mach–Zehnder and resonator‐based modulators are also discussed. Finally, future directions are outlined, including standardized characterization protocols, multi‐physics simulation platforms, alternative materials such as lithium tantalate, and emerging approaches like multiferroic skyrmion engineering. This review aims to guide the development of stable, reliable TFLN modulators for next‐generation photonic applications.