Experimental estimate of electron escape depth in Fe

Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy is a powerful experimental tool to investigate the electronic and atomic structure of materials. The great power of NEXAFS derives from its elemental specificity and symmetry selection rules. Because the various elements have different core level energies, NEXAFS permits extraction of the signal from a surface monolayer or even a single buried layer in the presence of a huge background signal. We have calculated electron escape depth ( λ e ) in Fe at the L2,3 edge using pure Fe thin films of different thickness by soft x-ray absorption spectroscopy measurements. We have recorded high-resolution x-ray absorption spectra in transmission of Fe thin films resolving the near edge x-ray absorption fine structure. As a conclusion we found the mean escape depth of emitted electrons to be λ e = 22 ± 2 Å . We believe our results provide important information for the improved understanding of theory of the photo absorption mechanism.