Model for transient behavior in field gradient propagation of bubbles

We propose a new model for the interpretation of pulsed field gradient propagation of bubbles, based on recent high-speed photography measurements in Eu-Ga-YIG films. We propose that dynamic conversion, i.e. Bloch curve nucleation and expansion, occurs consistently in our films during propagation, giving rise to motion at a saturation velocity of order 1000 cm/sec; large net displacements are achieved by a ballistic overshoot arising from the Bloch curve winding. Scatter and negative deviations of the net displacements from the theory occur because of incomplete unwinding of the Bloch curves.