Singh Robinjeet, Purdy Thomas P
Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA.
National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
Phys Rev Lett. 2020 Sep 18;125(12):120603. doi: 10.1103/PhysRevLett.125.120603.
Nanomechanical systems are generally embedded in a macroscopic environment where the sources of thermal noise are difficult to pinpoint. We engineer a silicon nitride membrane optomechanical resonator such that its thermal noise is acoustically driven by a spatially well-defined remote macroscopic bath. This bath acts as an acoustic blackbody emitting and absorbing acoustic radiation through the silicon substrate. Our optomechanical system acts as a sensitive detector for the blackbody temperature and for photoacoustic imaging. We demonstrate that the nanomechanical mode temperature is governed by the blackbody temperature and not by the local material temperature of the resonator. Our work presents a route to mitigate self-heating effects in optomechanical thermometry and other quantum optomechanics experiments, as well as acoustic communication in quantum information.
纳米机械系统通常嵌入在宏观环境中，在这种环境下热噪声源难以精确确定。我们设计了一种氮化硅膜光机械谐振器，使其热噪声由空间上定义明确的远程宏观热库通过声学方式驱动。这个热库充当声学黑体，通过硅衬底发射和吸收声辐射。我们的光机械系统充当黑体温度和光声成像的灵敏探测器。我们证明，纳米机械模式温度由黑体温度决定，而非由谐振器的局部材料温度决定。我们的工作为减轻光机械测温及其他量子光机械实验中的自热效应，以及量子信息中的声学通信提供了一条途径。
