Dielectric properties of I-III- VI 2 -type chalcopyrite semiconductors

Dielectric properties of I-III-${\mathrm{VI}}_{2}$-type ternary chalcopyrite semiconductors, including linear and second order nonlinear optical susceptibilities at 10.6 \ensuremath{\mu}m, have been quantitatively studied from the chemical bond viewpoint. Contributions from each type of constituent chemical bond, i.e., I $\char22{}$ VI and III $\char22{}$ VI bonds, to the total linear and nonlinear optical properties of these compounds at 10.6 \ensuremath{\mu}m have been theoretically determined. The chemical bond method quantitatively expresses the trends in the dielectric properties of these compounds, which is helpful for carrying out modeling of their properties.