On-chip erbium-doped lithium niobate microcavity laser

The commercialization of lithium niobate on insulator (LNOI) wafer has resulted in significant on-chip photonic integration application owing to its remarkable photonic, acousto-optic, electro-optic, and piezoelectric nature. In recent years, a variety of high-performance on-chip LNOI-based photonic devices have been realized. In this study, we developed a 1-mol% erbium-doped lithium niobate crystal and its LNOI on a silicon substrate and fabricated an erbium-doped LNOI microdisk with high quality factor (∼ 1.05×105). C-band laser emission at ∼1530 and ∼1560 nm (linewidth 0.12 nm) from the high-Q erbium-doped LNOI microdisk was demonstrated with 974- and 1460-nm pumping, with the latter having better thermal stability. This microlaser would play an important role in the photonic integrated circuits of the lithium niobate platform.