B.S.T.J. Briefs: A New Type of Cylindrical Magnetic Domain (Bubble Isomers)

Cylindrical magnetic domains (bubbles) are, by now, well known. Their device applications1 and theoretical description2 have been adequately described. We shall call these bubbles "normal" (NB). In this B.S.T.J. Brief we wish to describe a new type of cylindrical domain that can coexist in many of the materials that support NB's. They were first observed by R. F. Fischer and R. H. Morrow of Bell Laboratories while testing a Y-Bar shift register using a platelet cut f r o m bulk GdTblG. These d o m a i n s , which we shall call "hard" bubbles (HB), have properties that can be substantially different from NB's.