Magnetic anisotropy in arrays of nanometer-scale iron particles

Arrays of ferromagnetic iron particles have been fabricated by a combination of chemical vapor deposition and scanning tunneling microscopy. Hall magnetometry and MFM measurements have been used to determine their magnetic properties. The measured switching fields indicate magnetization reversal by curling from which an exchange length, /spl lambda//sub ex/=3.1 nm, may be estimated. The cylindrically shaped particles have an easy magnetization direction (EMD) along their long axis due to shape anisotropy. The magnetic anisotropy is evaluated by fitting calculated magnetization curves to those measured with applied field perpendicular to the particles EMD.