Advances in Low-Loss Thin-Film Lithium Niobate Photonic Integrated Devices

Abstract

Abstract: Recently, due to the rapid development of ion-slicing technique and low-loss nanostructuring technology for thin-film lithium niobate (TFLN), photonic integrated microstructures have been demonstrated on the TFLN platform with high-performances, allowing tight optical field confinement, ultralow propagation loss, fast electro-optic tunability, highly efficienct optical frequency conversion, and strong acousto-optic modulation. This technological advance in turn results in a variety of innovative photonic integrated devices of unprecedented optical qualities, such as meter-scale length electro-optically switchable optical true delay lines, ultrahigh-speed electro-optic modulators, efficienct frequency convertors, on-chip frequency combs, miniaturized microwave sources, bright quantum light sources, high-power waveguide amplifiers, narrow-linewidth microlasers, and compact ultrafast light sources. Up to now, the TFLN photonics is making a great advance in large-scale photonic integrated circuits, and opening an avenue for the further development for fast information processing, precision metrology, integrated quantum information processing and artificial intelligence, enabled by the advances in low-loss wafer-scale nanofabrication technology and the outstanding properties of TFLN. This review begins with the history of bulk lithium niobate optics, and then we survey the development history of ion-sliced TFLN wafer and nanofabrication technologies for TFLN photonic structures. The following sections present various TFLN photonic integrated devices categorized into nonlinear photonics, frequency comb generation, electro-optical modulators, wavelength/mode division multiplexers and coherent light sources. Finally, some conclusions and future perspectives are provided.

Key words: thin-film lithium niobate, nanofabrication, photonic integrated device, nonlinear photonics, electro-optical modulator, frequency comb generation

CLC Number:

O734

LIN Jintian, GAO Renhong, GUAN Jianglin, LI Chuntao, YAO Ni, CHENG Ya. Advances in Low-Loss Thin-Film Lithium Niobate Photonic Integrated Devices[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2024, 53(3): 372-394.

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