I have worked on this topic only during my stay as visiting scientist at
the ESRF in 1992 and shortly afterwards. Nevertheless, I am very proud
of this work:
X-Ray Resonant Magnetic Scattering from Surfaces
A. Fasolino, P. Carra, M. Altarelli,
Phys. Rev. B 47, 3877 (1993);J. Magn. and Magn. Mat. 121, 194 (1993).
We have proposed that X-ray resonant magnetic scattering could be combined
with X-ray surface crystallography to get information on the magnetic surface
structure. In analogy to the crystal truncation rods, one may also define
magnetic truncation rods aligned along the surface normal and passing through
the magnetic bulk Bragg reflections.
In 1992, intense light sources like the ESRF were not yet operational and the
local scientists were very skeptical about the possibility to observe such
pure magnetic crystal truncation rods. The very weak intensity of magnetic truncation rods together with
the need to work at very specific wavelengths at resonance with a transition
from a core level seemed an overwhelming challenge.
In 1996, in the Phys. Rev. Lett. 77 of july 22, two papers reported the
observation of surface resonant magnetic scattering.
Our derivation of the formula for the scattering cross section for X-ray Resonant Exchange Scattering (XRES) as first given
by: J. P. Hannon, G. T. Trammell, M. Blume and D.
Gibbs, Phys. Rev. Lett. 61 ,1245 (1988); 62, 2644(E) (1989).
It is not straightforward, please let us know if you find it useful.
X-Ray resonant exchange scattering from 3d transition metal
surfaces G.P. M. Poppe, A. Fasolino, Surf. Sci. 331-333, 1186
(1995).