BREAK DOWN OF VERTICAL-BLOCH-LINE CHAINS IN THE FIRST KIND OF DUMBBELL DOMAIN-WALLS SUBJECTED TO AN INPLANE FIELD

Experiments were statistically carried out on the behavior of the vert ical-Bloch-line (VBL) chains of the first hind of dumbbell domains (ID s) in garnet bubble films subjected to an in-plane field, H-ip. It was found that for IDs the critical in-plane field, (H'(ip))(ID), above w hich their VBL chains disappear, is the same as that of ordi nary hard bubbles (OHBs), H'(ip). However, for IDs, the critical range of H'(ip ), for VBL chain softening is larger than that of OHBs. Besides, we al so found some details of the softening process, e. g., the collapse fi eld range of the remaining IDs shrinks rapidly towards H-0,(max), and this very narrow range can maintain until all IDs are softened.