Net motion induced by nonantiperiodic vibratory or electrophoretic excitations with zero time average
Net motion induced by nonantiperiodic vibratory or electrophoretic excitations with zero time average
复制标题
零时间平均的非反周期振动或电泳激发引起的净运动
DOI：
10.1103/physreve.105.065001
复制
发表时间：
2022
影响因子：
2.4
通讯作者：
Miller, Gregory H.
中科院分区：
文献类型：
--
作者：
Hashemi, Aref;Tahernia, Mehrdad;Hui, Timothy C.;Ristenpart, William D.;Miller, Gregory H.
众所周知，采用时间平均为零但时间不对称的振荡激励可以产生净漂移。到目前为止，这种时间对称破缺和净漂移主要是在点粒子、非线性光学和量子系统的背景下探索的。在这里，我们提出了两个新的实验系统，其中宏观物体的机械运动可以很容易地观察到时间不对称力激发的影响：(1)放置在均匀平面上的厘米级固体物体使其横向振动，(2)放置在平行电极之间的水中的带电胶体粒子在外加振荡电位的情况下。在这两种情况下，在实验和数值上都观察到了非反周期双模正弦的净运动，其中频率模式是奇数和偶数的比率(例如，和)。对于相同的施加波形，观察到的运动方向总是相同的，并且很容易通过改变施加波形的符号来反转，例如，通过交换哪个电极通电和接地。我们将这些结果推广到其他非线性力学系统，并讨论了利用可调周期驱动力来方便地控制物体运动的意义。
It is well established that application of an oscillatory excitation with zero time-average but temporal asymmetry can yield net drift. To date this temporal symmetry breaking and net drift has been explored primarily in the context of point particles, nonlinear optics, and quantum systems. Here, we present two new experimental systems where the impact of temporally asymmetric force excitations can be readily observed with mechanical motion of macroscopic objects: (1) solid centimeter-scale objects placed on a uniform flat surface made to vibrate laterally, and (2) charged colloidal particles in water placed between parallel electrodes with an applied oscillatory electric potential. In both cases, net motion is observed both experimentally and numerically with nonantiperiodic, two-mode, sinusoids where the frequency modes are the ratio of odd and even numbers (e.g.,and). The observed direction of motion is always the same for the same applied waveform, and is readily reversed by changing the sign of the applied waveform, for example, by swapping which electrode is powered and grounded. We extend these results to other nonlinear mechanical systems, and we discuss the implications for facile control of object motion using tunable periodic driving forces.