Creep Kinematics of Cross‐tie Domain Walls

Abstract

Domain-wall creep was studied by the powder pattern method. To increase the resolution of the boundary pictures, microphotometry of the photographs was made. The centre of the boundary on the film was determined to a n accuracy of & 0.05 pm. The direct observation of elementary acts of creep enables to substantiate and refine the kinematic creep model -the model of varying boundary curvature. The curvature variation is due to the variation in the boundary rigidity as a result of the inductionof magnetostatic "charges".Das Kriechen von Domanenwanden wurde mit der Pulverdiagrammethode untersucht. Um die Auflosung der Bilder der Grenzen zu erhohen. wurden die Diagramme mikrophotometrisch ausgewertet. Das Zentrum der Grenze auf dem Film wurde mit einer Genauigkeit von &0,05 pm bestimmt. Die direkte Beobachtung der Elementarakte des Kriechens erlaubt, das kinematische Kriechmodell das Model1 der variierenden Grenzkurvenformen -zu erharten und zu verbessern. Die Anderung der Kurvenform wird durch die Anderung der Grenzstabilitat als Ergebnis einer Induktion magnetostatischer ,,Ladungen" verursacht.

Low Temperature Reversal in Anisotropic Ferromagnetic Films

“…2 shows micrographs of the actual 'viscous' motion of a crosstie wall. This low temperature motion in constant field proceeds very similar to wall creep a t 300 O K [17]. On applying a field smaller than the critical field for the 'viscous' wall motion to a crosstie wall a reversible response was observed.…”

“…At temperatures above 40 "K this reversible wall deflection was much less conspicuous, the deflection being a t most one third of the value below 15°K as was also found with the Bitter-technique 3, In order to reduce surface charges. [17]. There, however, the driving nature of the circle Bloch lines and the variation of the crossties could not be observed.…”