Figure 1

Underfocused (a),(d), in-focus (b),(e), and overfocused (c),(f) Lorentz TEM images of the plane view 10 nm thick $\mathrm{MnSi}/\mathrm{Si}(111)$ epitaxial thin film. (a)–(c) are for the magnetic helical phase under zero magnetic field, while (d)–(f) are for the Skyrmion formations under a magnetic field applied perpendicular to the film plane. $\mathrm{\Delta }f$ is the degree of defocus condition.