Applied Physics Letters · 2003 · 40 citations · 11 references
Natural SciencesMaterials EngineeringMaterials ScienceMagnetic MaterialsMaterials PhysicsThin FilmsEpitaxial GrowthMagnetic AnisotropyMagnetic Properties Of SolidsMagnetic Thin FilmsMagnetism In SolidsThin Film Magnetic PropertiesCoercivityEpitaxial Film GrowthEpitaxial Magnetic FilmsEpitaxial Thin-film GrowthIntrinsic PropertiesMagnetic CoercivityPulsed Laser DepositionSpin Reorientation
Epitaxial Nd2Fe14B films with the c axis (easy magnetization axis) perpendicular to the film plane were prepared on a Ta(110) buffer on single crystalline Al2O3(0001) substrates using pulsed laser deposition. Due to the epitaxial film growth an almost perfect alignment of all magnetic moments perpendicular to the film plane is achieved. Coercivities up to 2 T are obtained for Nd-rich films where the Nd2Fe14B grains are magnetically decoupled. An analysis of the coercivity mechanism shows that the switching mechanism is nucleation dominated and the high coercivity is achieved by avoiding nucleation within the grains. Intrinsic properties like the spin reorientation temperature of 135 K and spin reorientation angle of 30° at 4.2 K of these films are in very good agreement to single crystal data.
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