Bloch line memory: Dams for stripe domain confinement

Abstract

In the Bloch line memory, stripe domains are used as storage loops for vertical Bloch lines (VBL). In this paper we report on a technological solution for locally stabilizing these domains and also for setting a one-dimensional potential for VBL propagation by means of ion-milled grooves and dams. The changes in shape of the garnet film have been studied both theoretically and experimentally. The interaction of magnetic domains with topographic shaping of magnetostrictive (111) films are examined in detail in the case of a single groove. Stabilization margins are found to be related to the geometric data of topographic shaping, to the crystallographic orientation of the grooving edges, and to the magnetoelastic properties of the garnet film. Qualitative agreement with the prediction of the theoretical considerations is obtained from measurements on as grown (YSmLuCa)3(GeFe)5O12-garnet films with a periodical arrangement of grooves and dams, carried out by bias-field pulses margins with up to 130 Oe (tp=1 μs) without sweeping the domains from the region of the grooves to the dams.