Magnetic domain structure and magnetic anisotropy in ferromagnetic Y3Fe5O12 nanowires formed by step-edge decoration

We investigated the ferromagnetic properties of Y3Fe5O12 (yttrium iron garnet; YIG) nanowires deposited on a highly ordered pyrolytic graphite (HOPG) substrate. YIG nanowires with a diameter around 70 nm were formed on the edges of terraces of the HOPG substrate using the step-edge decoration technique and pulsed laser deposition of the YIG. The magnetic field of the YIG nanowires was investigated; a ferromagnetic hysteresis loop was observed in the direction parallel to the nanowires, whereas anti-ferromagnetic hysteresis loops were observed perpendicular to the nanowire growth direction. Vertical and lateral magnetic force microscopy images of the ferromagnetic YIG nanowires revealed that the magnetization directions of the nanowires were parallel to the nanowires, which showed a single ferromagnetic domain.