Kramers–Kronig transform for the surface energy loss function

• Published in: Journal of electron spectroscopy and related phenomena Vol. 142; no. 2; pp. 97 - 103
• Main Authors: Tan, G.L., DeNoyer, L.K., French, R.H., Guittet, M.J., Gautier-Soyer, M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-02-2005
• Subjects: Electronic structure; Lorentz oscillator model; REELS; SrTiO 3; Surface energy loss function; Surface Kramers–Kronig transform; SrTiO 3; Lorentz oscillator model; Electronic structure; REELS; Surface Kramers–Kronig transform; Surface energy loss function
• ISSN: 0368-2048; 1873-2526
• DOI: 10.1016/j.elspec.2004.09.002

A new pair of Kramers–Kronig (KK) dispersion relationships for the transformation of surface energy loss function Im[−1/(
ɛ
+
1)] has been proposed. The validity of the new surface KK transform is confirmed, using both a Lorentz oscillator model and the surface energy loss functions determined from the experimental complex dielectric function of SrTiO
3 and tungsten metal. The interband transition strength spectra (
J
cv) have been derived either directly from the original complex dielectric function or from the derived dielectric function obtained from the KK transform of the surface energy loss function. The original
J
cv trace and post-
J
cv trace overlapped together for the three modes, indicating that the new surface Kramers–Kronig dispersion relationship is valid for the surface energy loss function.