Optical properties of the defect-chalcopyrite-type semiconductor ZnIn2Te4 h
ave been studied by optical absorption, spectroscopic ellipsometry, and x-r
ay photoelectron spectroscopy. Optical absorption measurements suggest that
ZnIn2Te4 is a direct-gap semiconductor having a band gap of similar to 1.4
0 ev. The complex dielectric-function spectra epsilon (E)=epsilon (1)(E)+i
epsilon (2)(E), measured by spectroscopic ellipsometry, reveal distinct str
uctures at energies of the critical points in the Brillouin zone. Analysis
of the numerically derived epsilon (E) spectra facilitates the precise dete
rmination of the critical point parameters (energy position, strength, and
broadening). By performing the band-structure calculation, these critical p
oints are successfully assigned to specific points in the Brillouin zone. T
he measured x-ray photoelectron spectrum is also presented along with the d
ensity-of-states N(E) calculation.