论文标题
表面声子引起的纳米级固态齿轮的旋转耗散
Surface phonon induced rotational dissipation for nanoscale solid-state gears
论文作者
论文摘要
与翻译运动的纳米级摩擦相比，旋转摩擦的机制受到了较少的关注。对于通常涉及旋转齿轮的机械机械的微型化，这种运动成为一个重要的问题。在这项研究中，进行了分子动力学模拟，以探索在不同底物顶部旋转的固态齿轮的旋转摩擦。在每种情况下，都会观察到旋转运动的粘性阻尼，并发现齿轮和底物之间的纯Van-Waals相互作用引起。研究了不同齿轮尺寸和各种底物材料的影响。此外，发现齿轮和底物的刚性产生不同的耗散通道。最后，结果表明，对耗散的主要贡献与底物中低频表面形成量的激发有关。
Compared to nanoscale friction of translational motion, the mechanisms of rotational friction have received less attention. Such motion becomes an important issue for the miniaturization of mechanical machineries which often involve rotating gears. In this study, molecular dynamics simulations are performed to explore rotational friction for solid-state gears rotating on top of different substrates. In each case, viscous damping of the rotational motion is observed and found to be induced by the pure van-der-Waals interaction between gear and substrate. The influence of different gear sizes and various substrate materials is investigated. Furthermore, the rigidities of the gear and the substrate are found to give rise to different dissipation channels. Finally, it is shown that the dominant contribution to the dissipation is related to the excitation of low-frequency surface-phonons in the substrate.
