Molecular beam epitaxial growth of Bi2Se3 nanowires and nanoflakes

Abstract

Topological Insulators are in focus of immense research efforts and rapid scientific progress is obtained in that field. Bi2Se3 has proven to be a topological insulator material that provides a large band gap and a band structure with a single Dirac cone at the Gamma-point. This makes Bi2Se3 one of the most promising three dimensional topological insulator materials. While Bi2Se3 nanowires and nanoflakes so far were fabricated with different methods and for different purposes, we here present the first Bi2Se3 nanowires as well as nanoflakes grown by molecular beam epitaxy. The nanostructures were nucleated on pretreated, silicon (100) wafers. Altering the growth conditions nanoflakes could be fabricated instead of nanowires; both with high crystalline quality, confirmed by scanning electron microscopy as well as transmission electron microscopy. These nanostructures have promise for spintronic devices and Majorana fermion observation in contact to superconductor materials. (C) 2014 AIP Publishing LLC.