Shkarin A B, Kashkanova A D, Brown C D, Garcia S, Ott K, Reichel J, Harris J G E
Department of Physics, Yale University, New Haven, Connecticut 06520, USA.
Laboratoire Kastler Brossel, ENS-Université PSL, CNRS, Sorbonne Université, Collège de France 24 rue Lhomond, 75005 Paris, France.
Phys Rev Lett. 2019 Apr 19;122(15):153601. doi: 10.1103/PhysRevLett.122.153601.
We measure the quantum fluctuations of a single acoustic mode in a volume of superfluid He that is coupled to an optical cavity. Specifically, we monitor the Stokes and anti-Stokes light scattered by a standing acoustic wave that is confined by the cavity mirrors. The intensity of these signals (and their cross-correlation) exhibits the characteristic features of the acoustic wave's zero-point motion and the quantum backaction of the intracavity light. While these features are also observed in the vibrations of solid objects and ultracold atomic gases, their observation in superfluid He opens the possibility of exploiting the remarkable properties of this material to access new regimes of quantum optomechanics.
我们测量了与光学腔耦合的超流氦体积中单个声学模式的量子涨落。具体而言，我们监测由腔镜限制的驻声波散射的斯托克斯光和反斯托克斯光。这些信号的强度（及其互相关）展现出声波零点运动和腔内光量子反作用的特征。虽然在固体物体和超冷原子气体的振动中也观察到了这些特征，但在超流氦中的观察结果为利用这种材料的非凡特性进入量子光力学的新领域开辟了可能性。
