Angular Dispersion and its Relationship with Other Magnetic Parameters in Permalloy Films

Publisher Website
Google Scholar
Abstract
An experimental investigation has been made of the dispersion of the easy axis in Permalloy films deposited in an orienting field. The dispersion was studied as a function of the following parameters: reversible rotation limit Htr; easy direction coercive force Hc; anisotropy field Hk; and hard direction hysteresis loop squareness ratio (Mr/Ms)d, and coercive force (Hcd). Observations were made with a Kerr magneto‐optic apparatus and with a 1000‐cycle hysteresigraph. Angular dispersion of the easy axis, measured by the hysteresigraphic method, was found to increase with Hc/Hk. Reversible rotation limit was not found to decrease with increasing angular dispersion as predicted by theory, but rather to decrease more rapidly initially with increasing dispersion and then to increase again at larger dispersion. The initial effect is believed to be due to the influence of local variation of Hk on the reversible rotation measurement. There is some indication that hard direction coercive force increases with increasing dispersion, but there seems to be no simple correlation between dispersion and hard direction hysteretic properties. Reversible rotation limit was found to be roughly proportional to coercive force in most films, except those which exhibit an unusual type of wall motion switching behavior.

This publication has 5 references indexed in Scilit: