A study of magnetic interactions of Ni80Fe20 arrays using ultra-sensitive microcantilever torque magnetometry
Lan Gao, D. Q. Feng, L. Yuan, T. Yokota, R. Sabirianov, Sy-Hwang Liou, Michelle Chabot, Daniel Porpora, John M. Moreland
We have successfully fabricated single and paired 300 nm × 1.5 υm × 32 nm Ni80Fe20 bars on a microcantilever using focused ion beam milling. Magnetic interactions of these paired bars were studied by using magnetic force microscopy, microcantilever torque magnetometry and micromagnetic simulation. Our results clearly indicate that the magnetic switching behavior of the paired Ni80Fe20 bars is affected by magnetostatic interactions. The M-H hysteresis curves for a sample with 8 pairs of Ni80Fe20 bars consists of a series of stable switching states that are related to the domain wall motion in the bars.