CONDUCTION-BAND STATES AND SURFACE CORE EXCITONS IN INSB(110) AND OTHER III-V COMPOUNDS

Angle-resolved constant-initial-state spectroscopy from the valence-band maximum (VBM) as the initial state was used to determine the conduction-band energies at the Gamma point up to 30 eV above the VBM for InSb. Structure in the spectra up to 20 eV could be assigned to particular interband transitions by comparison with empirical pseudopotential calculations. Autoionizing resonances due to surface core excitons have been observed. From their energies a surface-core-exciton binding energy of 0.5 eV for InSb has been determined. Both results are discussed in light of our previous work on the conduction-band states and surface core exditons of several III-V semiconductors.