Figure 7: Colossal STT effect of bound pair of skyrmions in case (B1).

(a) Current (j) – velocity (v) characteristics of skyrmion bound state (see text). The black broken line indicates the universal relation v = j by dimensionless v and j²⁶. (b) Device structure. (c) Skyrmion structure on layer 1 for j = 0, J_inter/J_intra = −0.1 and K/J_intra = 0.06 (corresponding to the red curve in (a)). A closeup at 100 × 100 area (see the length scale) is presented. (d) The same as (c) but for j = 2.0 × 10¹¹ A/m². To represent the magnetic textures (c,d), the color code (e) is used.