Related papers: Gas Doping on the Topological Insulator Bi2Se3 Sur…

Recently an air-stable layered semiconductor Bi2O2Se was discovered to exhibit an ultrahigh mobility in transistors fabricated with its thin layers. In this work, we explored the mechanism that induces the high mobility and distinguishes…

Although topological surface states are known to be robust against non-magnetic surface perturbations, their band dispersions and spatial distributions are still sensitive to the surface defects. Take Bi2Se3 as an example, we demonstrated…

Topological insulators embody a new state of matter characterized entirely by the topological invariants of the bulk electronic structure rather than any form of spontaneously broken symmetry. Unlike the 2D quantum Hall or quantum…

Using scanning tunneling spectroscopy we have studied the effects of nitrogen gas exposure on the bismuth selenide density of states. We observe a shift in the Dirac point which is qualitatively consistent with theoretical modeling of…

The Cu-doped topological insulator Bi$_2$Se$_3$ has recently been found to undergo a superconducting transition upon cooling, raising the possibilities that it is the first known "topological superconductor" or realizes a novel non-Abelian…

The observation of helical surface states in Bi-based three-dimensional topological insulators has been a challenge since their theoretical prediction. The main issue raises when the Fermi level shifts deep into the bulk conduction band due…

Bi$_{2}$Se$_{3}$ is a topological insulator whose unique properties result from topological surface states (TSS) in the band gap. Low energy ion scattering can determine the properties of the outermost few atomic layers of a solid. The…

We report an unexpected positive hydrostatic pressure derivative of the superconducting transition temperature in the doped topological insulator \NBS via $dc$ SQUID magnetometry in pressures up to 0.6 GPa. This result is contrary to…

Topological insulators embody a newly discovered state of matter characterized by conducting spin-momentum locked surface states that span the bulk band gap. So far, most of the study on topological insulator surfaces has been limited to…

Rubidium adsorption on the surface of the topological insulator Bi$_2$Se$_3$ is found to induce a strong downward band bending, leading to the appearance of a quantum-confined two dimensional electron gas states (2DEGs) in the conduction…

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…

In2O3 is an n-type transparent semiconducting oxide possessing a surface electron accumulation layer (SEAL) like several other relevant semiconductors, such as InAs, InN, SnO2, and ZnO. Even though the SEAL is within the core of the…

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…

Magnetic doping with transition metal ions is the most widely used approach to break timereversal symmetry in a topological insulator, a prerequisite for unlocking the TIs exotic potential. Recently, we reported the doping of Bi2Te3 thin…

Doping of the ultrawide band gap semicodnctor LiGaO$_2$ ($E_g=5.6$ eV) with N$_2$, NO and O$_2$ molecules placed in either Ga or Li-vacancies is studied using first-principles calculations. These molecular dopants are considered as…

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…

Homojunctions between Bi$_2$Se$_3$ and its Mn-doped phase are investigated as a sample geometry to study the influence of spin degrees of freedom on topological insulator properties. $n$ quintuple layers (QLs) of Bi$_2$Se$_3$ are grown…

The recently discovered topological insulators exhibit topologically protected metallic surface states which are interesting from the fundamental point of view and could be useful for various applications if an appropriate electronic gating…

Topological insulators possess completely different spin-orbit coupled bulk and surface electronic spectra that are each predicted to exhibit exotic responses to light. Here we report time-resolved fundamental and second harmonic optical…

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…