Opt Express. 2023 Apr 10;31(8):13040-13052. doi: 10.1364/OE.484369.
We present a highly reflective, sub-wavelength-thick membrane resonator featuring high mechanical quality factor and discuss its applicability for cavity optomechanics. The 88.5 nm thin stoichiometric silicon-nitride membrane, designed and fabricated to combine 2D-photonic and phononic crystal patterns, reaches reflectivities up to 99.89 % and a mechanical quality factor of 2.9 × 10 at room temperature. We construct a Fabry-Perot-type optical cavity, with the membrane forming one terminating mirror. The optical beam shape in cavity transmission shows a stark deviation from a simple Gaussian mode-shape, consistent with theoretical predictions. We demonstrate optomechanical sideband cooling to mK-mode temperatures, starting from room temperature. At higher intracavity powers we observe an optomechanically induced optical bistability. The demonstrated device has potential to reach high cooperativities at low light levels desirable, for example, for optomechanical sensing and squeezing applications or fundamental studies in cavity quantum optomechanics; and meets the requirements for cooling to the quantum ground state of mechanical motion from room temperature.
我们提出了一种高度反射、亚波长厚的膜谐振器，具有高机械品质因数，并讨论了其在腔光机械中的应用。88.5nm 厚的化学计量比硅-氮化硅膜，设计并制作成结合二维光子和声子晶体图案，达到了高达 99.89%的反射率和 2.9×10 的室温机械品质因数。我们构建了一种法布里-珀罗型光学腔，其中膜形成一个终止反射镜。腔透射中的光束形状与理论预测一致，明显偏离简单的高斯模形状。我们从室温开始演示了机械侧带冷却到 mK 模式温度。在更高的腔内功率下，我们观察到光机械诱导的光学双稳性。所展示的器件有望在低光水平下达到高协同性，例如，用于光机械传感和压缩应用或腔量子光机械学中的基础研究；并满足从室温冷却到机械运动量子基态的要求。
