Slippage and Boundary Layer Probed in an Almost Ideal Gas by a Nanomechanical Oscillator
Slippage and Boundary Layer Probed in an Almost Ideal Gas by a Nanomechanical Oscillator
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DOI：
10.1103/physrevlett.113.136101
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发表时间：
2014-09-23
影响因子：
8.6
通讯作者：
Collin, E.
中科院分区：
文献类型：
--
作者：
Defoort, M.;Lulla, K. J.;Collin, E.
我们测量了He-4气体在4.2 K和高质量的纳米机电弦设备之间的相互作用，其前三个对称模式（谐振频率为2.2，6.7和11 MHz，品质因数Q > 0.1 x 10（6））超过近6个数量级的压力。这种流体可以被看作是一个几乎理想的单原子和惰性气体，其属性列表的最佳实验实施。实验的范围从高压的流动是层流斯托克斯型的滑移下降到非常低的压力下的流动是分子。在分子制度，当平均自由路径的顺序之间的距离悬浮的纳米机械探针和沟槽的底部，我们解决了第一次的签名的边界（努森）层到测量的耗散。我们的研究结果进行了讨论的最新理论调查的框架内的边界效应的流体（分析方法和直接模拟蒙特卡罗方法）。
We measure the interaction between He-4 gas at 4.2 K and a high-quality nanoelectromechanical string device for its first three symmetric modes (resonating at 2.2, 6.7, and 11 MHz with quality factor Q > 0.1 x 10(6)) over almost 6 orders of magnitude in pressure. This fluid can be viewed as the best experimental implementation of an almost ideal monoatomic and inert gas of which properties are tabulated. The experiment ranges from high pressure where the flow is of laminar Stokes-type presenting slippage down to very low pressures where the flow is molecular. In the molecular regime, when the mean-free path is of the order of the distance between the suspended nanomechanical probe and the bottom of the trench, we resolve for the first time the signature of the boundary (Knudsen) layer onto the measured dissipation. Our results are discussed in the framework of the most recent theories investigating boundary effects in fluids (both analytic approaches and direct simulation Monte Carlo methods).