Optimal molar fractions of ternary zinc-blende terahertz emitters

Abstract

We report our calculation of optimal molar fractions in various ternary zinc-blende terahertz emitters that can produce terahertz radiation with enhanced powers when the wavelength of the pump laser is changed. While the momentum mismatch between the optical and the terahertz pulses in these non-resonant nonlinear materials was mainly used to understand the spectral and the transient shapes of the generated terahertz waves, the optimal molar fractions in compound semiconductor terahertz emitters were better determined with the full numerical calculations. To demonstrate the output power change and the sensitivity of the calculation, we performed numerical simulations of the optical rectification process during the optical and the terahertz wave propagations. The result suggests that the optimal Cd compositions in Zn1-x,CdxTe are x = 0.10 at lambda = 820 nm and x = 0.65 at lambda = 850 nm and that the Te compositions in ZnSe1-xTex are x = 0.6 at lambda = 750 nm and x = 0.95 at lambda = 820 nm. This method could act as a powerful tool to optimally design various zinc-blende semiconductor compounds to generate terahertz waveforms.