Determination of the Effective Ionic Charge of Gallium Arsenide from Direct Measurements of the Dielectric Constant

Direct measurements of static and optical dielectric constants have been made on GaAs with a resistivity of 109 ohm cm at room temperature. Values obtained were 0 = 12.5(3) and ∞ = 10.90. An effective ionic charge es* of 0.46e can be deduced from these values.