Figure 1.
Schematic representation of experimental setup. Circular ferromagnetic permalloy disks are lithographically patterned on a silicon surface. Also shown are the vectorial maps from OOMMF simulations of the magnetic configurations using a cell size of 50 nm over disks 5 μm in diameter by 40 nm thick in the presence of Hx = 50 Oe are shown along with the disks. The magnetization profiles are tuned by four remotely controlled electromagnets that produce rotating in-plane fields Hx and Hy. Reversible perpendicular fields, Hz, are produced by the circular solenoid coil. Movements of cells are recorded by an optical microscope (Reichert) with a 20× objective and high-speed camera.