EFFECT OF DAMPING ON DYNAMIC DISTORTION IN MAGNETIC GARNET MATERIAL

Damping has a large effect on,the dynamic character of domain walls in bubble garnet material with structure within the walls. When a step c hange in bias field is applied to a wall containing a pi VBL chain or a 2 pi VBL chain, the VBL velocity makes large changes in magnitude fo r the first 50 nsec when the damping is 0.1 and smoothly changes when the damping is 0.5. Dynamic distortion of 2 pi VBL also makes large sw ings in magnitude for low damping. Because the wall and VBL velocity a s well as 2 pi VBL distortion change so markedly with time for low dam ping, it is clear-that an increase in damping above the traditional al pha=0.1 is very desirable for material used in a VBL memory.