Spatially resolved magnetic reversal in a multilayered exchange bias system

We have observed the magnetic reversal of an exchange bias model system on both sides of the ferromagnet/antiferromagnet (FM/AFM) interface via nuclear resonant scattering of synchrotron radiation from 57Fe sensor layers. This method yields the spin direction and the fraction of uncompensated moments with nm depth resolution. The reversal of the ferromagnet along the easy axis proceeds via the formation of a domain structure that extends across the FM/AFM interface. This is responsible for archetypal exchange bias characteristics like the small magnitude of the bias and the asymmetric shape of the hysteresis loop.