Figure 1. Structural characteristics and X-ray imaging of domain patterns.

(a) Out-of-plane hysteresis loop for a companion multilayer film grown on Si wafer. The magnetic moment is normalized to its saturation magnetization M_S=9 × 10⁵ A m⁻¹. The inset shows both in-plane and out-of-plane hysteresis loops for a Pt/CoFeB/MgO unit layer grown on Si wafer. (b) Series of magnetic transmission soft X-ray microscopy (MTXM) images acquired for increasing field B_z>0. Dark and light contrast corresponds to down (−z)- and up (+z)-oriented magnetization directions, respectively. Scale bar, 200 nm. (c) MTXM image acquired at B_z=+25 mT and the schematic of the expected chiral magnetic textures.