Domain Structure of Narrow Thin Films of Ni-Fe

Abstract

Narrow thin films of 80 Ni‐20 Fe were produced by evaporation onto a glass substrate with a mask having several slits. The films were 15∼300 μ wide, 400∼1500 Å thick, and 4∼80 Oe in H_K perpendicular to their long direction. Bitter patterns on the films having H_K of several Oe showed the closure domains as proposed by Kittel. The energy density of the 180° walls between the adjacent main domains was measured to be 0.8 erg/cm², by observing the spacing of the walls and the width of the films. The films having higher H_K did not exhibit closure domains but only 180° walls parallel to the easy axis, as was also proposed by Kittel. By bending the substrate mechanically, H_K was increased in the films having closure domains. The transition, from the structure of closure domains into that of no closure domains, was observed as expected.