Synthesis and Characterization of Te2SeO7: A Powder Second-Harmonic-Generating Study of TeO2, Te2SeO7, Te2O5, and TeSeO4

The synthesis and characterization of a noncentrosymmetric tellurium selenate, Te2SeO7, is reported. In addition, the powder second-harmonic-generating (SHG) properties of TeO2, Te2SeO7, Te2O5, and TeSeO4 have been measured, using 1064 nm radiation. Through the powder SHG experiments, we are able to determine that TeO2 is not phase-matchable, whereas Te2SeO7, Te2O5, and TeSeO4 are phase-matchable. Also, TeO2, Te2SeO7, Te2O5, and TeSeO4 have SHG efficiencies of 5, 200, 400, and 400 times SiO2, respectively. The relative SHG efficiencies may be understood by examining the structure of each material. Through the powder SHG measurements, we estimate the average nonlinear optical bond susceptibility, 〈d2ωijk〉, for each material.