Jg. Tobin et al., MAGNETIC-X-RAY CIRCULAR-DICHROISM IN PHOTOELECTRON-SPECTROSCOPY AND DIFFRACTION, Surface review and letters, 3(3), 1996, pp. 1429-1448
In this paper, we discuss a series of photoelectron-spectroscopy (PS)
and photoelectron-diffraction (PD) studies utilizing magnetic x-ray ci
rcular dichroism and fully spin-specific, multiple-scattering calculat
ions for analysis of the experimental results. The test system used wa
s perpendicularly magnetized, ferromagnetic monolayer Fe/Cu(001), prep
ared and probed at low temperature. Two sets of states were used: the
Fe2p at binding energies of over 700 eV (large spin-orbit and small ex
change splittings) and the Fe3p at a binding energy of near 53 eV (spi
n-orbit and exchange splittings approximately equal). The PS and PD me
asurements made were angularly resolving and compared to calculational
results which were similarly angularly dependent. Both ''exchange shi
fts'' and intensity variations of spectral structure were observed. Th
e impact of ''j-state mixing'' was seen in both the Fe2p and 3p spectr
a. Our results indicate a ferromagnetically ordered FCC Fe with a latt
ice parameter near that of bulk Cu. Nevertheless, the sensitivity of t
he multiple-scattering calculations of both the Fe2p and Fe3p simulati
ons to local order has been used to show that the overlayer structure
posseses some level of imperfection or disorder as well.