X-ray magnetic circular dichroism and element-selective magnetic hysteresis in Fe/Cu/Co/Cu multilayers

X-ray magnetic circular dichroism using x-ray phase retarders in the hard x-ray region

“…Then, it appears reasonable to expect that the ESMH response at both the K-and L 2,3 -edges of the transition metal should be different, the same holding for the L 2 -and M 4,5 -edges of the rare-earth. This proposition is in agreement with previous results obtained at the L 3 - [131] and at the K-edges [132] of Co in Fe/Cu/Co multilayers, for which the coercive fields obtained by ESMH differs one order of magnitude. Initially, the discrepancy was addressed to different deposition conditions of the samples, although the macroscopic magnetic behavior was similar in both cases [131,132].…”

“…This proposition is in agreement with previous results obtained at the L 3 - [131] and at the K-edges [132] of Co in Fe/Cu/Co multilayers, for which the coercive fields obtained by ESMH differs one order of magnitude. Initially, the discrepancy was addressed to different deposition conditions of the samples, although the macroscopic magnetic behavior was similar in both cases [131,132]. Our previous results points out that this disagreement might be due to the fact that the ESMH cycles depend not only on the atomic species selected in the XMCD measurements, but also on the particular absorption edge tuned.…”

“…It is inherently assumed that the ESMH cycles obtained for the same atomic species in a given material should be the same no matter the absorption edge tuned. However, the results obtained through this Thesis and a critical reexamination of previous results [131,132] suggest that this simple view of the ESMH is not correct.…”

Anomalous magnetic hysteresis of Gd and Fe moments in a Gd/Fe multilayer measured by hard x-ray magnetic circular dichroism

“…On the other hand, hard x rays penetrate deeply, and hard x-ray MCD will not be much sensitive to the surface condition, and probes bulk property. 22 Although the surface phase transition is triggered by a few outer layers as mentioned above, it would exert its influence on the inner layers to some extent. Then, the present hard x-ray MCD has shown the canted region in this sample permeating deeply into the inside.…”

X-ray magnetic circular dichroism with tunable polarization helicity

“…The XMCD obtained in this way is identical to that obtained by reversing the direction of the magnetic ®eld. The advantage of this method is that the magnetic ®eld becomes a variable parameter: XMCD spectra can be measured as a function of magnetic ®eld intensity and, for example, element-selective hysteresis cycles can be measured (Pizzini et al, 1997).…”