Influence of in-plane field on vertical Bloch line in the walls of the second kind of dumbbell domains at various temperatures

Abstract The stability of vertical Bloch lines (VBLs) in the second kind of dumbbell domain (IIDs) walls in liquid phase epitaxy garnet bubble films subjected to an in-plane field at various temperatures is studied experimentally. It is found that there exists a critical in-plane field range depending on temperature, in which vertical Bloch lines (VBLs) in the second kind of IIDs walls are unstable, i.e., [ H ip ( 1 ) ( T ) , H ip ( 2 ) ( T ) ] . Here, H ip ( 1 ) ( T ) is the initial critical in-plane field at which VBLs in the walls of IIDs annihilate; while H ip ( 2 ) ( T ) is the lowest in-plane field at which all VBLs in the walls of IIDs have annihilated completely. Also, the critical in-plane field range [ H ip ( 1 ) ( T ) , H ip ( 2 ) ( T ) ] , H ip ( 1 ) ( T ) and H ip ( 2 ) ( T ) all decrease with the temperature increasing. H ip ( 1 ) ( T ) and H ip ( 2 ) ( T ) reach zero at T 0 ′ and T 0 , respectively.