The preparation process and feature of the topological insulator Bi2Te3

摘要

Abstract Topological insulators are insulating in the bulk but have metallic surface states. Its unique physicochemical properties can find numerous applications in electronics, spintronics, photonics, the energy sciences, and the signal control of transportation. We report an experimental approach to synthesize the high-quality single crystal of topological insulator Bi~(2)Te~(3) by using self-flux method. We obtained the optimal preparation conditions by adjusting the parameters of heat treatment, and successfully prepared the single-crystal Bi~(2)Te~(3) sample. The as-grown samples have a surface with bright metallic luster and are soft and fragile. Furthermore, Bi~(2)Te~(3) has the obvious layer structure from SEM results. The data of X-ray diffraction and scanning electron microscope show that Bi~(2)Te~(3) single crystal grows along the c -axis with the order of Te_((1))–Bi–Te_((2))–Bi–Te_((1)) and crystallizes in the hexagonal system with space group of R/3?m. The ρ – T curve shows that ρ decreases with temperature, showing metallic behavior over the whole temperature range.