脉冲偏场作用下石榴石磁泡薄膜中布洛赫线的形成

The formation of vertical Bloch line in the garnet bubble films subjected to pulsed bias field

实验研究了石榴石磁泡薄膜中不同脉冲宽度下产生的硬磁畴的动态特性.结果表明:由零偏场下产生的枝状畴收缩而成的哑铃畴均逆时针转动,与产生枝状畴时所用的脉冲偏场的脉冲宽度无关.而固定直流偏场下由软畴段硬化而成的哑铃畴的转动状态,则与所用的硬化脉冲偏场的脉冲宽度有关.低脉冲宽度下硬化成的哑铃畴均逆时针转动,随硬化脉冲宽度的升高,出现混合转动向顺时针转动的过渡.由此揭示了直流偏场和脉冲偏场在石榴石磁泡薄膜中形成正、负垂直布洛赫线的作用.

We studied experimentally the dynamic characteristics of hard domains produced in the garnet bubble films at different pulse widths.The results show that the dumbbell domains contracted from multi-branched domains at zero static bias field rotate clockwise,independent of the pulse width of the pulsed bias field in which the multi-branched domains were produced.In the direct current fixed bias fields,soft domain segments harden and become dumbbell domains.How the dumbbell domains rotate is dependent on the pulse widths of the hardening pulsed bias field applied in the experiment.The results show that all the dumbbell domains rotate anticlockwise when the pulse width is narrow,and they rotate clockwise and anticlockwise simultaneously and then they all rotate clockwise as the width of hardening pulse becomes wider and wider.It reveals that the direct current bias field and pulsed bias field have great influence on the types of vertical Bloch line in the garnet bubble films.