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Domain wall image widening was discovered in epitaxial garnet films during bubble domain radial expansion using high-speed photography /1 t o 3/. This present study investigates DDW over a wide range of drive field. The experiments were performed on (Y, Yb, Bi, Gd)3(Fe, A1I3Ol2 film grown by LPE on a (111 )-oriented GGG substrate. The film had a thickness h = 25 ym, stripe domain period Po = 47 p m , collapse field Ho = 50 Oe, coercivity Hc = 0.6 Oe, characteristic length 1 = 2.5 pm, saturation magnetization 4 PI Ms = 95 G, an-3 3 isotropy field Hk = 1700 Oe, and unaixal anisotropy constant Ku = 6x1 0 erg/cm .The well-known relationships

The domain wall velocity of ion-implanted garnet films is measured on expanding stripe domains observed—using a laser-flash optical microscope, for wide drive field and temperature range. Comparison of measured and calculated velocities shows the insufficiency of present theories. A simple model is suggested for describing the saturation velocity phenomena in implanted garnet films. This model shows the wall structure distortion at the effective films surfaces to be approximated by a transient Bloch line zone. The average static azimuthal angle is assumed to be ψ̄0=π2Λ0/D in good agreement with the experimentally obtained ψ̄0=11.8 Λ0/D, where D is the effective film thickness and Λ0 is the Bloch line width parameter. The calculated saturation velocities agree surprisingly well with the experimental results for wide thickness and temperature range.