Direct evidence of imprinted vortex states in the antiferromagnet of exchange biased microdisks

The magnetic domain structure of patterned antiferromagnetic/ferromagnetic Ir20Mn80/Ni80Fe20 bilayer microdisk arrays has been investigated using layer-specific polarized x-ray photoemission electron microscopy and magnetic circular dichroism. Magnetic imaging at the Fe and Mn L-edge resonances provided direct evidence of a vortex state imprinted into the antiferromagnet at the interface. The opposite magnetic contrast between the layers indicated a reversed chirality of the imprinted vortex state, and a quantitative analysis of the magnetic moment from the dichroism spectra showed that uncompensated Mn spins equivalent to about 60% of a monolayer of bulk Ir20Mn80 contributed to the imprinted information at the interface.
QC 20110418 Korrigering: This article was originally published online and in print with an error in the fifth author’s name in Ref. 13; the correctspelling of the author’s name should have been E. Menéndez. AIP apologizes for this error. All online versions of the articlehave been corrected.