Vortex control in PacMan nanodots

Control of vortex chirality and polarity in magnetic nanodots with broken rotational symmetry.
V. Cambel, and G. Karapetrov
Phys. Rev. B 84, 014424 (2011)

Hysteresis curve of a “Pac-Man”-like Py nanodot with an outer diameter of 70 nm, an inner diameter of 46 nm,
and a thickness of 40 nm.