Long-Range Domain Wall Tension in Pt/Co/Pt Films with Perpendicular Magnetic Anisotropy

Abstract

We report an experimental detection of a long-range tension effect on magnetic domain walls in Pt/Co/Pt films. Such a tension effect is observed from circular domains expanding (or shrinking) under a constant applied magnetic field. Interestingly, the domain propagation speed varies with respect to the domain radius. Converting the speed variation to a magnetic field via the creep scaling, it is revealed that there exists an effective field inversely proportional to the radius, in accordance with the domain wall tension and the magnetostatic dipolar interaction. The sizeable tension effect subsists over 20 mu m, providing a way to directly determine the wall energy density. (C) 2011 The Japan Society of Applied Physics