Accession Number : AD0432825


Title :   TORQUE AND ROTATIONAL HYSTERESIS IN FCC SINGLE CRYSTAL COBALT FILMS,


Corporate Author : FRANKLIN INST PHILADELPHIA PA


Personal Author(s) : Doyle,William D


Report Date : Dec 1963


Pagination or Media Count : 11


Abstract : The Stoner-Wohlfarth coherent rotation model is extended to the case of biaxial anisotropy. The rotational hysteresis integral W equals 1.54. Measurements on fcc single crystal Co films (-k = 4 - 6 x 105 ergs/cc) prepared by epitaxial evaporation onto the (100) face of single crystal MgO slabs held at 400 C yield results in wide disagreement with the theory. While the expected angular symmetry of the torque is observed the model does not correctly predict the magnitude of the torque nor the fields at which specific types of angular dependence will be observed. The magnetization reversal process in single crystal Co films is not coherent and that as in the case of polycrystalline films noncoherent rotations or wall motions must be investigated. This situation in single element, single crystal films calls for a reappraisal of the importance of compositional inhomogeneities, and local crystalline anisotropy in polycrystalline alloy films. (Author)


Descriptors :   *COBALT , *SINGLE CRYSTALS , METAL FILMS , SYMMETRY(CRYSTALLOGRAPHY) , HYSTERESIS , ANISOTROPY , EPITAXIAL GROWTH , ALLOYS , FERROMAGNETIC MATERIALS , TORQUE , ROTATION , THICKNESS , ELECTRON DIFFRACTION


Distribution Statement : APPROVED FOR PUBLIC RELEASE