Environmentally stabilized crystalline WGM resonator

We report on the development of a packaged optical whispering-gallery-mode (WGM) resonator exhibiting low vibration sensitivity. The fractional frequency shift is measured to be on the order of 10^-10/<i>g</i> along the vertical axis and 10^-11/<i>g</i> along the horizontal axis. The resonator, operating in the optical domain with an intrinsic quality factor of <i>Q</i>∼10⁹, is employed for laser frequency stabilization. The resulting laser exhibited a relative frequency stability 3×10^-12 level at 10 ms integration time. These results highlight the potential of optical WGM resonators as compact, mechanically robust frequency references for precision photonic systems.