Related papers: Magnetic Doping and Kondo Effect in Bi2Se3 Nanorib…
Bi2Se3 is a prototypical topological insulator which has a small band gap (~0.3 eV) and topologically protected conducting surface states. This material exhibits quite strong thermoelectric effects. Here we show in a mechanically exfoliated…
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…
Bismuth selenide (Bi2Se3) is a good topological insulator (TI) with its surface band Dirac point inside the bulk bandgap. However, Bi2Se3 films grown by molecular beam epitaxy (MBE) often require tuning of Fermi level near the Dirac point…
Rare earth ions typically exhibit larger magnetic moments than transition metal ions and thus promise the opening of a wider exchange gap in the Dirac surface states of topological insulators. Yet, in a recent photoemission study of…
Three-dimensional topological insulators (TIs) have emerged as a unique state of quantum matter and generated enormous interests in condensed matter physics. The surfaces of a three dimensional (3D) TI are composed of a massless Dirac cone,…
Gas molecule doping on the topological insulator Bi2 Se3 surface with existing Se vacancies is investigated using first-principles calculations. Consistent with experiments, NO2 and O2 are found to occupy the Se vacancy sites, remove…
Bi2Se3 is theoretically predicted1 2and experimentally observed2,3 to be a three dimensional topological insulator. For possible applications, it is important to understand the electronic structure of the planar device. In this work,…
A combined experimental and theoretical study of doping individual Fe atoms into Bi2Se3 is presented. It is shown through a scanning tunneling microscopy study that single Fe atoms initially located at hollow sites on top of the surface…
The development of nanoscale solid-state devices exploiting the promising topological surface states of topological insulator materials requires careful device engineering and improved materials quality. For instance, the introduction of a…
We combine low energy muon spin rotation (LE-$\mu$SR) and soft-X-ray angle-resolved photoemission spectroscopy (SX-ARPES) to study the magnetic and electronic properties of magnetically doped topological insulators, (Bi,Sb)$_2$Te$_3$. We…
Magnetic doping is expected to open a band gap at the Dirac point of topological insulators by breaking time-reversal symmetry and to enable novel topological phases. Epitaxial (Bi$_{1-x}$Mn$_{x}$)$_{2}$Se$_{3}$ is a prototypical magnetic…
We show that by Ca-doping the Bi2Se3 topological insulator, the Fermi level can be fine tuned to fall inside the band gap and therefore suppress the bulk conductivity. Non-metallic Bi2Se3 crystals are obtained. On the other hand, the Bi2Se3…
Recently, A2B3 type strong spin orbital coupling compounds such as Bi2Te3, Bi2Se3 and Sb2Te3 were theoretically predicated to be topological insulators and demonstrated through experimental efforts. The counterpart compound Sb2Se3 on the…
Magnetically doped topological insulators enable the quantum anomalous Hall effect (QAHE) which provides quantized edge states for lossless charge transport applications. The edge states are hosted by a magnetic energy gap at the Dirac…
Three-dimensional (3D) topological insulators are known for their strong spin-orbit coupling and the existence of spin-textured topological surface states which could be potentially exploited for spintronics. Here, we investigate spin…
We show that a three dimensional topological insulator doped with magnetic impurities in the bulk can have a regime where the surface is magnetically ordered but the bulk is not. This is in contrast to conventional materials where bulk…
Based on a self-consistent $t$-matrix approximation, we explore the influence of magnetic and nonmagnetic doping on the surface electronic states and conductivity of topological insulators. We show that warping parameter has a crucial…
We discuss the possibility of realizing Weyl semimetal phase in the magnetically doped topological band insulators. When the magnetic moments are ferromagnetically polarized, we show that there are three phases in the system upon the…
Electron irradiation is investigated as a way to dope the topological insulator Bi2Te3. For this, p-type Bi2Te3 single crystals have been irradiated with 2.5 MeV electrons at room temperature and electrical measurements have been performed…
With a large band gap and a single Dirac cone responsible for the topological surface states, Bi2Se3 is widely regarded as a prototypical 3D topological insulator. Further applications of the bulk material has, however, been hindered by…