Integrated lithium niobate photonics and applications

Over the last decade, the availability of high-quality thin-film lithium niobate (TFLN) and breakthroughs in nanofabrication techniques have enabled numerous integrated, efficient, and high-performance components with unique functionalities. Here, I will demonstrate several strategies for integrating lasers on TFLN platform which can lead to new opportunities in telecommunication, microwave photonics, and sensing. demonstrate high-performance and ultra-low loss devices in the thin-film lithium niobate platform for applications such as gas spectroscopy and data communication. First, we build a dual-comb interferometer based on cavity-based electro-optic frequency combs. With this, we perform a proof-of-concept spectrally-tailored multiplexed sensing benefits from the frequency stability of the comb sources. Next, I design an integrated electro-optic comb with ultra-dense comb spacing down to hundreds of MHz. I then introduce a modification to convectional TFLN fabrication (post-fabrication annealing, and carefully selecting the cladding material), which improves the minimum achievable loss on this platform by almost an order of magnitude. Our response measurement (self-calibrated via the Kerr nonlinearity) reveals that the intrinsic absorption-limited Q-factor on TFLN platform can be as high as 165 million opening door for transformative classical and quantum devices. In the end, I demonstrate a fully-integrated electrically-driven high-power laser transmitter on TFLN with more ~ 100 GHz bandwidth. This method allows for coupling more than 115 mW of optical power into thin-film lithium niobate waveguides. Finally, I discuss our novel technique for scalable laser integration and arbitrary THz waveform synthesis in TFLN platform.