Lorentz microscopy on amorphous films with perpendicular anisotropy as a function of temperature

The EM study of amorphous magnetic thin films of GdCoX (X = Au, Mo) as a function of temperature shows that Q, the ratio of perpendicular anisotropy Ku to the square of the magnetization Ms, is inversely proportional to temperature. Generally, for any film with a given Ku both in‐plane and perpendicular domain structures are observed at RT and their proportional appearance is a direct measure of Q. Furthermore, their interaction at the proper Q value, coupled to externally applied bias and pulsed fields, leads to strip and bubble formation. Since Q can be increased inversely with temperature and Ku is a function of film deposition, a proper temperature can be found for varying film compositions at which bubble ormation will take place. Copyright © 1976 WILEY‐VCH Verlag GmbH & Co. KGaA