Co islands by STM

Magnetic properties of monolayer Co islands on Ir(111) probed by spin-resolved scanning tunneling microscopy.
Jessica E. Bickel, Focko Meier, Jens Brede, André Kubetzka, Kirsten von Bergmann, and Roland Wiesendanger
Phys. Rev. B 84, 054454 (2011)

(a), (b), (e), (f) Spin-resolved dI/dU images. Note: (b) is a zoomed area from image (a) with opposite
tip magnetization direction. (c) Hysteresis curve taken from the area shown in (b).