On-chip erbium-doped lithium niobate microdisk lasers

Erbium-doped lithium niobate high-Q microdisk cavities were fabricated in batches by UV exposure, inductively coupled plasma reactive ion etching and chemo-mechanical polishing. The stimulated emission at 1531.6 nm was observed under the pump of a narrow-band laser working at 974 nm in erbium-doped lithium niobate microdisk cavity with threshold down to 400 {\mu}W and a conversion efficiency of 3.1{\times}10^{-4} %, laying the foundation for the LNOI integrated light source research.