High-resolution electron energy-loss measurements performed in situ on GaAS(001)-c(4 x 4) surfaces grown by molecular beam epitaxy reveal a number of intrinsic features so far unobserved. The one-to-one correspondence found between experimental and calculated electronic transitions provides for the first time a satisfactory understanding of the electronic properties of this prototype surface. The optical surface anisotropy originates entirely from very few atomic layers beneath the surface. This gives to the energy-loss anisotropy data two orders of magnitude higher surface sensitivity than that of reflectance difference spectroscopies. (C) 2002 Elsevier Science B.V. All rights reserved.
The GaAs(0 0 1)- c(4 × 4) surface: A new perspective from energy loss spectra / Balzarotti, A.; Fanfoni, M.; Patella, F.; Arciprete, F.; Placidi, E.; Onida, G.; Del Sole, R.. - In: SURFACE SCIENCE. - ISSN 0039-6028. - 524:1-3(2003), pp. L71-L76. [10.1016/S0039-6028(02)02540-2]