Influence of in-plane field on the critical temperature for the breakdown of vertical Bloch line chains

Abstract

The influence of in-plane field Hip on the critical temperature To for the breakdown of vertical Bloch line (VBL) chains of hard domains in garnet bubble films has been investigated experimentally. It was found that To can be significantly reduced by the increase of Hip. Besides, the critical in-plane field H'ip for the breakdown of VBL chains was measured as a function of temperature T for the same sample. As a result, the correlation between these two critical parameters, To and H'ip, was found. By introducing an effective inplane field (Hip)e, the positive definiteness of the system of VBL pairs with two-dimensional magnetization distribution was analyzed, giving rise to a theoretical expression of H'ip (T): H'ip (T) =|4πMsQ(ao + a1Q + a2Q2 + a3Q3 + a4Q4)|T(To)Hip=o, where ai are constants. It agrees well with the experiments.