Absence of dynamic conversion of bubbles in Permalloy-coated garnet films of (YGdTm)3 (FeGa)5O12

Abstract

The scatter in the bubble velocity has been investigated in Permalloy‐coated garnet films of high‐mobility (YGdTm)₃ (FeGa)₅O₁₂. When Permalloy layers are 80 Å thick, the scatter does not exist even if the bias field is near the bubble run‐out field. This shows that the dynamic conversion does not occur in these films. When Permalloy layers become thicker than 120 Å, however, bubble velocities deviate to low values and show large scatter. The scatter in this case is due to pinning of planar domain walls of the Permalloy layer associated with bubbles.