Measurements of the electrooptic effect in CdS, ZnTe, and GaAs at 10.6 microns

Low-frequency electrooptic coefficients have been measured for three semiconductors at 10.5 microns. The results arerc = (5.5 ± 1) × 10⁻¹²m/V for CdS,r₄₁ = (1.4 ± 0.2) × 10⁻¹²m/V for ZnTe, andr₄₁ = (1.6 ± 0.1) × 10⁻¹²m/V for GaAs. A comparison is made of the efficiencies of these materials in different modulator configurations. The effect of photoelectrically induced space charge is discussed briefly.