Accurate optical constants of ZnTe measured by THz-TDS with their standard deviations

Accurate optical constants of the ZnTe are essential to optimize its performance as a terahertz emitter and detector. We measured the optical constants like complex refractive index of ZnTe crystal using transmission terahertz time domain spectroscopy (THz-TDS) from 0.2 to 3.5 THz at room temperature and their standard deviation is calculated to quantify the random errors. The uncertainty in sample thickness measurement, which is important to consider especially in transmission THz-TDS, is also incorporated to compute the resultant standard deviations in all optical constants. The percentage errors of real and imaginary parts of refractive index at 1 THz are 0.01 and 1.22 respectively.