An empirical relation for the saturation velocity in bubble domain garnet materials

An empirical relation is given for the saturation velocity of a domain wall in a bubble domain garnet material. The relation isvₒ₃ = 0.4π(A/Kᵤ)1/2, whereVₒ₃is the saturation velocity, γ the gyromagnetic ratio,4 saturation magnetization, A the exchange constant and Kuthe uniaxial anisotropy constant. The relation provides a close approximation for a wide range of experimental data. Comparisons between experimental data and theoretical data are made. A possible interpretation of the empirical relation is given.