The formation of 360° domain walls in magnetic tunnel junction elements

Abstract

The formation of 360° domain walls has been observed in exchange-biased magnetic tunnel junction elements using Lorentz transmission electron microscopy. These domain walls occur under certain circumstances and remain stable up to a high external field (∼150 Oe) compared to the value observed to achieve the antiparallel state of the free- and pinned-layer magnetizations (∼20 Oe). They have been found to play an important role during reversal to the parallel magnetization state, inducing a much lower switching field and a very different reversal mechanism.