Determination of the dependence of the band-gap energy on composition for ${\mathrm{Cd}}_{1\mathrm{-}\mathit{x}}$${\mathrm{Zn}}_{\mathit{x}}$Te

We have grown ${\mathrm{Cd}}_{1\mathrm{-}\mathit{x}}$ ${\mathrm{Zn}}_{\mathit{x}}$Te layers over the entire composition range (0≤x≤1) by molecular-beam epitaxy on GaAs(100) substrates. The quality of the layers is good near the end points of the alloy range but decreases in the middle as expected. We have obtained a relationship for the band-gap energy at 4 K as a function of Zn concentration. This relationship exhibits significantly larger bowing than was previously thought.