“…4,7,8 In addition, a depth-varying exchange-bias behavior in an ultrathin Co layer, sandwiched between a Pd capping layer and an antiferromagnetic FeMn layer, was observed in an earlier work. 9 Visible light or x-ray magneto-optical (MO) effects, such as the Kerr rotation K and ellipticity K , have been widely used to investigate a rich variety of magnetic states in magnetic heterostructures, because the MO effect is significantly sensitive to the small amount of magnetic moments in their magnitude and direction. [10][11][12][13][14][15][16] In particular, a synchrotron x-ray MO spectroscopy is emerging as a powerful cuttingedge technique, becoming a popular method to investigate the various magnetic properties being associated with nanostructures because of its several unique characteristics such as element specificity, magnetic sensitivity, and large resonant enhancement in the vicinity of the absorption edges, as well as the ongoing growths in the measurement and/or analysis techniques.…”