Related papers: Density Functional Study of Ternary Topological In…
(Bi$_{1-x}$Sb$_x$)$_2$Te$_3$ alloys are non-degenerate topological insulators (TIs) whose Dirac point (DP) can be tuned within the bulk bandgap by varying the composition, effectively reducing bulk conduction while allowing surface carrier…
Topological insulators represent a novel state of matter with surface charge carriers having a massless Dirac dispersion and locked helical spin polarization. Many exciting experiments have been proposed by theory, yet, their execution have…
Scanning tunneling microscopy and spectroscopy have been used to investigate the femtosecond dynamics of Dirac fermions in the topological insulator Bi$_2$Se$_3$ ultrathin films. At two-dimensional limit, bulk electrons becomes quantized…
Several small-bandgap semiconductors are now known to have protected metallic surface states as a consequence of the topology of the bulk electron wavefunctions. The known "topological insulators" with this behavior include the important…
Alloys of Bi$_2$Te$_3$ and Sb$_2$Te$_3$ ((Bi$_{1-x}$Sb$_x$)$_2$Te$_3$) have played an essential role in the exploration of topological surface states, allowing us to study phenomena that would otherwise be obscured by bulk contributions to…
We use real-time reflection high energy electron diffraction intensity oscillation to establish the Te-rich growth dynamics of topological insulator thin films of Bi2Te3 on Si(111) substrate by molecular beam epitaxy. In situ angle resolved…
An important challenge in the field of topological materials is to carefully disentangle the electronic transport contribution of the topological surface states from that of the bulk. For Bi$_2$Te$_3$ topological insulator samples, bulk…
We present an analysis of bulk and surface electronic structures of thallium based ternary III-V-VI$_2$ series of compounds TlMQ$_2$, where M=Bi or Sb and Q=S, Se or Te, using the ab initio density functional theory framework. Based on…
We discuss the magnetic and topological properties of bulk crystals and quasi-two-dimensional thin films formed by stacking intrinsic magnetized topological insulator ( for example Mn(Sb$_{x}$Bi$_{1-x}$)$_2$X$_4$ with X = Se,Te, including…
Using a density functional based electronic structure method, we study the effect of perturbations on the surface state Dirac cone of a strong topological insulator Bi$_2$Se$_3$ from both the intrinsic and extrinsic sources. We consider…
Using a density functional based electronic structure method, we study the effect of crystalline dielectrics on the metallic surface states of Bismuth- and chalcogen-based binary and ternary three dimensional topological insulator (TI) thin…
We present a comprehensive study of the crystal structure of the thin-film, ferromagnetic topological insulator (Bi, Sb)$_{2-x}$V$_x$Te$_3$. The dissipationless quantum anomalous Hall edge states it manifests are of particular interest for…
In an ideal 3D topological insulator (TI), the bulk is insulating and the surface conducting due to the existence of metallic states that are localized on the surface; these are the topological surface states. Quaternary Bi-based compounds…
Tensile strained bulk HgTe is a three-dimensional topological insulator. Because of the energetic position of its surface state Dirac points relative to its small bulk gap, the electronic properties of the relatively thin MBE-grown films…
Topological insulators are distinguished from normal insulators by their bulk insulating gap and odd number of surface states connecting the inverted conduction and valence bands and showing Dirac cones at the time-reversal invariant points…
We report the successful formation of bulk insulating ternary topological insulators candidate Bi2Se2Te (BST) by pulsed laser deposition technique. The films were deposited with sequential ablation of separate Bi2Se3 (BS) and Bi2Te3 (BT)…
We have designed three-dimensional models of topological insulator thin films, showing a tunability of the odd number of Dirac cones on opposite surfaces driven by the atomic-scale geometry at the boundaries. This enables creation of a…
Transient reflectivity (TR) from thin films (6 - 40 nm thick) of the topological insulator Bi2Se3 reveal ultrafast carrier dynamics, which suggest the existence of both radiative and non-radiative recombination between electrons residing in…
We have performed high-resolution angle-resolved photoemission spectroscopy on TlBiSe2, which is a member of the ternary chalcogenides theoretically proposed as candidates for a new class of three-dimensional topological insulators. By…
We discuss possible topological phase transitions in Ge-based thin films of Ge(Bi$_x$Sb$_{1-x}$)$_2$Te$_4$ as a function of layer thickness and Bi concentration $x$ using the first principles density functional theory framework. The bulk…