1 research outputs found
Band Structure Engineering in Topological Insulator Based Heterostructures
The ability to engineer an electronic
band structure of topological
insulators would allow the production of topological materials with
tailor-made properties. Using ab initio calculations, we show a promising
way to control the conducting surface state in topological insulator
based heterostructures representing an insulator ultrathin films on
the topological insulator substrates. Because of a specific relation
between work functions and band gaps of the topological insulator
substrate and the insulator ultrathin film overlayer, a sizable shift
of the Dirac point occurs resulting in a significant increase in the
number of the topological surface state charge carriers as compared
to that of the substrate itself. Such an effect can also be realized
by applying the external electric field that allows a gradual tuning
of the topological surface state. A simultaneous use of both approaches
makes it possible to obtain a topological insulator based heterostructure
with a highly tunable topological surface state