Near-IR comparative characterization of optical second-order nonlinearities in Te-based semiconductors

We have systematically characterized the second harmonic generation efficiency of Te-based binary and ternary II-VI compounds in the near-IR spectral region, namely at lambda = 1.5 mum and lambda = 1.9 mum. A phase mismatched technique has been employed, as a translation into the spectral domain of the Maker fringes method. By using sub-picosecond optical pulses, reliable results for the value of non second-order linear coefficient d and of chromatic dispersion have been obtained. We have performed a comparative evaluation of nonlinear wavelength conversion efficiency of Te-based semiconductors and GaAs. The ternary alloys Cd0.5Zn0.5Te and Cd0.78Mn0.22Te can be considered as the best performing basic materials for optical wavelength converters working in the third communication window, since they possess at the same time a high d coefficient, good transparency, and low chromatic dispersion.