Tunable single-mode lasing on a high-Q resonator

https://phys.org/news/2022-07-tunable-single-mode-lasing-high-q-resonator.html 

"polygon modes coherently combined by multiple WGMs triggered by weak perturbation from tapered fiber... modes sparse within optical gain bandwidth compared to WGM counterpart... Q factors remain ultrahigh (~10 million)... single frequency lasing... linewidth narrow as 322 Hz... real-time electro-optical tuning of the microlaser wavelength, thanks to the strong linear electro-optic coefficient of LN; the research team demonstrated a high tuning efficiency of ∼50 pm/100V"