Fe nanomagnets with unusual size-dependent magnetizationdirections produced by fast laser-induced self-organization

摘要

ABSTRACTLaser-induced melting of ultrathin films can lead to self-organized arrays of hemispherical particles. We have applied this procedure to assemble arrays of Fe nanomagnets on SiO_2 substrates. Morphological studies showed presence ofspatial short range order (SRO) in the array. Magnetic properties were studied at room temperature using zero-fieldmagnetic force microscopy (MFM). The particles upto 55 nm in diameter showed in-plane (45°), compared to out-of-plane magnetization directions (45°) for the larger particles. The size-dependent orientation of magnetization forthese hemispherical particles, was attributed to the dominating magnetostrictive energy and a size-dependent residual strain.