相关论文: Band bending at interfaces between topological ins…
The unique properties of spin-polarized surface or edge states in topological insulators (TIs) make these quantum coherent systems interesting from the point of view of both fundamental physics and their implementation in low power…
Thin (6-7 quintuple layer) topological insulator Bi2Se3 quantum dot devices are demonstrated using ultrathin (2~4 quintuple layer) Bi2Se3 regions to realize semiconducting barriers which may be tuned from Ohmic to tunneling conduction via…
Three-dimensional (3-D) topological insulators (TI) are characterized by the presence of metallic surface states and a bulk band gap. Recently theoretical and experimental studies have shown an induced gap in the surface state bands of TI…
Shubnikov-de-Haas oscillations were studied under high magnetic field in Bi$_2$Se$_3$ nanostructures grown by Chemical Vapor Transport, for different bulk carrier densities ranging from $3\times10^{19}\text{cm}^{-3}$ to…
We have performed angle-resolved photoemission spectroscopy on (PbSe)5(Bi2Se3)3m, which forms a natural multilayer heterostructure consisting of a topological insulator (TI) and an ordinary insulator. For m = 2, we observed a gapped…
In the recently discovered class of materials known as topological insulators, the presence of strong spin-orbit coupling causes certain topological invariants in the bulk to differ from their values in vacuum. The sudden change of…
We performed broadband optical transmission measurements of Bi2Se3 and In-doped Bi(1-x)In(x)2Se3 thin films, where in the latter the spin-orbit coupling (SOC) strength can be tuned by introducing In. Drude and interband transitions exhibit…
One of the hallmarks of topological insulators is the correspondence between the value of its bulk topological invariant and the number of topologically protected edge modes observed in a finite-sized sample. This bulk-boundary…
Topological insulators are novel quantum materials with metallic surface transport, but insulating bulk behavior. Often, topological insulators are dominated by bulk contributions due to defect induced bulk carriers, making it difficult to…
Angle-resolved photoelectron spectroscopy is used for a detailed study of the electronic structure of the topological insulator Bi2Se3. Nominally stoichiometric and calcium-doped samples were investigated. The pristine surface shows the…
The topological insulating phase results from inversion of the band gap due to spin-orbit coupling at an odd number of time-reversal symmetric points. In Bi$_2$Se$_3$, this inversion occurs at the $\Gamma$ point. For bulk Bi$_2$Se$_3$, we…
We theoretically study the electronic structure and spin properties of one-dimensional nanostructures of the prototypical bulk topological insulator Bi$_2$Se$_3$. Realistic models of experimentally observed Bi$_2$Se$_3$ nanowires and…
A scheme is proposed to electrically measure the spin-momentum coupling in the topological insulator surface state by injection of spin polarized electrons from silicon. As a first approach, devices were fabricated consisting of thin…
The phase transition from a topological insulator to a trivial band insulator is studied by angle-resoled photoemission spectroscopy on Bi$_{2-x}$In$_{x}$Se$_{3}$ single crystals. We first report the complete evolution of the bulk band…
Topological insulators are materials with an insulating bulk interior while maintaining gapless boundary states against back scattering. Bi$_2$Se$_3$ is a prototypical topological insulator with a Dirac-cone surface state around $\Gamma$.…
A topological insulator possesses a bulk energy gap splitting the lowest empty band from the highest occupied electronic band. The electronic states at the surface (or edge in two dimensions), on the other hand, of a topological insulator…
Three dimensional topological insulator crystals consist of an insulating bulk enclosed by metallic surfaces, and detailed theoretical predictions about the surface state band topology and spin texture are available. While several…
Topological materials have been discovered so far largely by searching for existing compounds in crystallographic databases, but there are potentially new topological materials with desirable features that have not been synthesized. One of…
In this Letter we present scanning tunneling microscopy density-of-states measurements and electronic structure calculations of the topological insulator Bi2Se3. The measurements show significant background states in addition to the…
Gapless surface states on topological insulators are protected from elastic scattering on non-magnetic impurities which makes them promising candidates for low-power electronic applications. However, for wide-spread applications, these…