Tahir Mukarram A, Gao Lu, Virgin Lawrence N, Yellen Benjamin B
Duke University, Department of Mechanical Engineering and Materials Science, Center for Biologically Inspired Materials and Materials Systems, Durham, North Carolina 27708, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Jul;84(1 Pt 1):011403. doi: 10.1103/PhysRevE.84.011403. Epub 2011 Jul 26.
The nonlinear dynamic behavior of superparamagnetic beads transported through a two-dimensional potential energy landscape is explored empirically and through numerical simulation. The beads are driven through a periodic array of micromagnets by an external rotating field oriented at an angle θ relative to the magnetization direction of the substrate. The bead's motion was highly sensitive to the angle of the driving field near critical angles and to various system parameters, including bead size, rotation frequency, and substrate pole density. Our results suggest the possibility of using this behavior in a highly discriminative colloidal separation system, in which two different bead types can be tuned to move in orthogonal directions.
通过实验和数值模拟探索了超顺磁性珠子在二维势能景观中传输的非线性动力学行为。珠子由相对于基底磁化方向成角度θ的外部旋转场驱动通过微磁体的周期性阵列。珠子的运动在临界角附近对驱动场的角度以及各种系统参数（包括珠子尺寸、旋转频率和基底磁极密度）高度敏感。我们的结果表明，有可能在一种高度有区分性的胶体分离系统中利用这种行为，在该系统中可以调整两种不同类型的珠子使其沿正交方向移动。
