Lončar, MarkoHu, Evelyn LYeh, Matthew2026-06-0920262026-06-052026Yeh, Matthew. 2026. Materials-Motivated Engineering of the Thin-Film Lithium Niobate Quantum Electro-Optic Platform. Doctoral Dissertation, Harvard University Graduate School of Arts and Sciences.32702255https://dash.harvard.edu/handle/1/42740456The electro-optic effect, in which an applied electric field changes a material’s refractive index, provides a direct bridge between electronic and optical signals. Spurred by recent advances in nanofabrication, integrated electro-optics has had great success revolutionizing commercial markets for telecommunications and is expected to play a critical role in emerging applications such as quantum networks and photonic quantum computing. In this dissertation, I present two perspectives on leveraging the strong electro-optic coupling in a characteristic material platform, thin-film lithium niobate (TFLN). In Chapter 1, I provide a philosophical overview of the structure-property-performance relationships that govern materials science, and what it means for engineering to be "materials-motivated". In Chapter 2, I summarize the background theory of electro-optics required for the studies in this dissertation. In Chapters 3 and 4, I will describe the development of cavity-based electro-optic devices inspired by atomic and solid-state physics and their application to efficient spectral manipulation of light for quantum optics experiments such as two-photon interference. In Chapters 5 and 6, I will discuss materials challenges facing the stable dc biasing of such electro-optic devices, and progress toward sensing characteristic sources of drift and instability at material interfaces. By simply changing perspectives to a defect-oriented interpretation more characteristic of well-established semiconductor engineering, we can gain fundamental insights and new approaches into the microscopic origins and possible mitigation techniques for these nonidealities.application/pdfenDC driftDefectLithium NiobatePhotonicsQuantumApplied physicsOpticsMaterials ScienceThesis or Dissertation2026-06-090000-0001-8711-6505