This thesis delves into innovative active photonic integrated devices and circuits on the thin-film lithium niobate (TFLN) platform, focusing on their applications and potential future advancements. We introduce a new family of electrooptic modulators (EOMs), the Four-Phase Electrooptic Modulators (FEOMs), which are fabricated using the TFLN platform. These devices effectively mitigate bandwidth and dynamic-range constraints in optical communication systems by reducing dispersion penalties and common-mode noises. Their functionality is demonstrated in a photonic time-stretch system. A dual-polarization variant further exemplifies the mitigation of both dispersion penalties and common-mode noises in long-haul communication links, marking significant strides towards the practical implementation of coherent optical communication. We also engineer dual-channel, tunable ultra-narrow linewidth filters using phase-shifted Bragg grating structures on the TFLN platform. These filters act as key components for optical communication, sensing systems, and emerging quantum photonic applications. The device boasts a high extinction ratio, closely spaced channels with narrow linewidths, and efficient central wavelength tuning via the electrooptic effect. This makes it beneficial for finely adjusting high-precision photonic integrated circuits (PICs). The experimental results align well with the design and simulations, indicating promising potential for integration into advanced PICs for future quantum photonic applications and the development of multiple-channel ultra-narrowband filters with active tuning capabilities. Additionally, the thesis includes the design and simulation of a fully packaged TFLN EOM, catering to the rising demand for high-performance optical modulators in telecom and RF photonics applications. Lastly, we delve into a pioneering micro-electromechanical systems (MEMS) photonic switch that uses TFLN, harnessing LN's piezoelectric properties and outstanding operational bandwidth. These features have the potential to propel significant advancements in optical communication systems and other fields that necessitate precise light signal control.


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Graduation Date





Fathpour, Sasan


Doctor of Philosophy (Ph.D.)


College of Optics and Photonics


Optics and Photonics

Degree Program

Optics and Photonics


CFE0009893; DP0028426





Release Date

February 2024

Length of Campus-only Access


Access Status

Doctoral Dissertation (Open Access)