Soft X-ray magnetic circular dichroism and magnetic films

Abstract

Soft X-ray magnetic circular dichroism is the difference in the total absorption cross-section of positive and negative helicity circularly-polarized soft X-rays at the magnetically interesting L 2 and L 3 absorption edges of 3d transition metals or the M 4 and M 5 absorption edges of the rare earths. The absorption edges can be measured using a variety of techniques including transmission, partial electron yield, total electron yield, partial fluorescence yield, sample current, and reflection. The different measurement schemes represent different probing depths, allowing depth dependent studies, and are complementary to each other. A description of the relative merits of the various measurement schemes is presented. In addition, complications such as beam instability, saturation effect, and incident beam Bragg scattering into the detectors are discussed.