6 research outputs found
Observation of a Highly Spin Polarized Topological Surface State in GeBiTe
Spin polarization of a topological surface state for GeBiTe, the
newly discovered three-dimensional topological insulator, has been studied by
means of the state of the art spin- and angle-resolved photoemission
spectroscopy. It has been revealed that the disorder in the crystal has a minor
effect on the surface state spin polarization and it exceeds 75% near the Dirac
point in the bulk energy gap region (180 meV). This new finding for
GeBiTe promises not only to realize a highly spin polarized surface
isolated transport but to add new functionality to its thermoelectric and
thermomagnetic properties.Comment: 5 pages, 4 figure
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. © 2013 American Chemical Society.We acknowledge support by the Ministry of Education and Science of the Russian Federation (state task No. 2.8575.2013), the Federal Targeted Program “Scientific and scientific-pedagogical personnel of innovative Russia in 2009-2013” (No. 14.B37.21.1164) and Russian Foundation for Basic Research (Grant 13-02-12110 ofi_m). A.E. acknowledges funding by the German Research Foundation (DFG Grants ER 340/4-1 and the Priority Program 1666 “Topological Insulators”).Peer Reviewe
Band structure engineering in topological insulator based heterostructures
ABSTRACT: The ability to engineer an electronic ban
Band structure engineering in topological insulator based heterostructures
ABSTRACT: The ability to engineer an electronic ban
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