Fig. 2
From: Formation and current-induced motion of synthetic antiferromagnetic skyrmion bubbles
Current-induced motion of synthetic antiferromagnetic skyrmion bubbles. a Magnetic state of synthetic antiferromagnetically coupled wire obtained with magneto-optical polar Kerr effect microscopy under current pulse applications at μ0Hz = 0.2 mT. Each skyrmion is featured by different colors. Current density and pulse width are 7.1 × 1011 A m−2 and 1 μs, respectively. b Current density dependence of average velocity of skyrmion bubbles in stacks 1 (synthetic antiferromagnet) and 2 (ferromagnet), represented by blue and red, respectively. For stack 1, results with various pulse widths are plotted by different symbols. c The same result shown by a logarithm scale for vertical axis. d The same result focused in a low-current-density region
