Fabrication of Bi$_{2}$Te$_{3}$ Nanodots by Droplet Epitaxy on GaAs substrates

Bi$_{2}$Te$_{3}$, as a three-dimensional topological insulator, causes wide attention. Here, we report the fabrication of Bi$_{2}$Te$_{3}$ nanodots on GaAs substrate by droplet epitaxy using molecular beam epitaxy (MBE). Reflection high energy electron diffraction (RHEED), atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS), and Raman measurement revealed the existence of Bi$_{2}$Te$_{3}$ nanodots. Several approaches were developed to control the size and density of as-grown Bi$_{2}$Te$_{3}$ nanodots. Temperature and density dependent magneto-transport measurements were investigated. This may provide a platform for the interaction investigation among topological insulators, semiconductors, ferromagnets and superconductors.