The behavior of vertical-Bloch-line chains originating from a group of soft domain segments

In the story of the worldwide investigation and fabrication of solid magnetic memories during the period from 1967 to 1992, China was not absent. In the early 1970's, eleven people in the group of magnetic bubbles at the Institute of Physics, Chinese Academy of Sciences, began to investigate garnet bubble films. At that time the author was responsible for measuring the films, and thus designed and constructed a bubble measurement apparatus. To characterize these films, a group of soft magnetic segments, the so-called H pattern, was found, and a project to form hard bubbles by pulsed bias fields was established. This enabled the author to withstand the impact of the decision to abandon magnetic bubble memory research in the early 1980's, and then to learn the vertical-Bloch-line memory scheme put forward in 1983. The scheme made the author realize that we already had the conditions to study its mechanism, and, as a result, our papers signaled the end of vertical-Bloch-line memories. Finally, we were invited to present a review for the 100th commemorative volume of the Journal of Magn. Magn. Mater. in 1991; the article was one of the total of 32 invited reviews and the only one signed "China". <br<Since 1992, 25 years have passed. However, the lively bubble domains still exist and the once scrapped bubble apparatus has been renovated. It is hoped that college students and those newly entering the field of magnetism and magnetic materials will enjoy this research-orientated apparatus, which can show the vibrant moving bubbles and be used to explain the fundamental theories of ferromagnetism.