Superconducting FeSe1-xTex Single Crystals Grown by Optical Zone-Melting Technique

A new approach to grow FeSe1-xTex single crystals with an optical zone-melting technique was successfully employed. Crystals with actual composition 0.4 <= x <= 1.0 all show high crystallinity with no phase separation. The ability to visually observe the locally heated melt, and case of use and coil trol of the image furnace make this method a promising and time-efficient way for obtaining high-quality FeSe1-xTex crystals. Our results indicate that with adequate heat treatment, the nonuniform distribution of Se and Te atoms in crystal lattice can be effectively eliminated, while the transition Width of superconductivity call be reduced to about 2 K, which Suggest the crystals arc homogeneous in nature.