Surendra B. Anantharaman, Joachim Kohlbrecher, et al.
MRS Fall Meeting 2020
We have measured k-resolved inverse-photoemission spectra of the Ge(111)2×1 and Si(111)2×1 surfaces. The main spectral features are well described in terms of direct transitions to the three lowest conduction bands along ΓL and a transition to a surface resonance near the conduction-band minimum via a surface umklapp process. An extra feature reflects a maximum in the density of empty states. Several critical points are determined, e.g., for Ge, L1 at 0.7 eV, L3 at 4.2 eV, and L2' at 7.9 eV and a higher L point at 11 eV, and for Si, L1 at 2.4 eV and L3 at 4.15 eV above the valence-band maximum. By comparing our inverse-photoemission results with those from photoemission and optical spectroscopy we find that the E1 transition could be lowered by the electron-hole interaction by up to 0.15 eV for Ge and 0.5 eV for Si. A comparison with first-principles and empirical band calculations is made. © 1986 The American Physical Society.
Surendra B. Anantharaman, Joachim Kohlbrecher, et al.
MRS Fall Meeting 2020
Andreas C. Cangellaris, Karen M. Coperich, et al.
EMC 2001
Sharee J. McNab, Richard J. Blaikie
Materials Research Society Symposium - Proceedings
I.K. Pour, D.J. Krajnovich, et al.
SPIE Optical Materials for High Average Power Lasers 1992