Manipulation of Magnetic Nano-Particles with Strain Mediated Multiferroics

Strain mediated multiferroic systems provide an energy-efficient path to the manipulation of magnetic nano-particles for small scale mechanical, electrical, and biological applications. In this system, there is a magnetoleastic disk, a piezoelectric substrate and soft magnetic nano particles near the disk. The simulation consists of 1) voltage generated piezo-strains; 2) disk magnetic spin reorientation; and 3) the dynamic nano-particle movement. The particle dynamic model includes both translation and rotation considering: magnetic force, fluid drag, frictional force. The particle movement is studied for three dynamic cases with different frictional and drag coefficients: underdamped, critically damped and over damped. When the frictional and drag forces are small, the particle follows the rotation with a lag angle at steady state. The lag angle highly depends on the rotating frequency and the frictional/drag coefficients. When the frictional and drag forces further increase, the particle detaches from the disk when a critical velocity is reached. This work provides guidance on how to implement magnetic particle manipulation for a wide range of applications.