Erbium-Doped Aluminium Oxide Based Distributed Feedback Waveguide Laser in Thin Film Lithium Niobate Platform

As the realization of a series of high-performance lithium niobate (LN) photonic integrated devices, LN has become one of the most promising platforms for photonic integrated circuits. While the highly compatible LN based on chip light sources are still lacking. It is an urgent need to develop Cband light source on LN chips. We theoretically studied an erbium-doped <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{Al}_{2} \mathrm{O}_{3}$</tex> waveguide laser based on distributed feedback (DFB) cavity in the thin film lithium niobate (TFLN) platform. By utilizing chalcogenide glass (CHG) as the cladding material in a sandwich structure, a high confinement factor (52.5 %) and laser power is attained. The Laser is pumped at 1480 nm and exhibit fundamental TE mode at 1533 nm, with lasers yield efficiencies up to 27.1 % and lasering threshold as low as 4.4 mW in a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$10-\text{mm}$</tex>-long DFB cavity.