Related papers: Visualizing topological insulating Bi2Te3 quintupl…
We explore the phonon dynamics of thin films of the topological insulator material Bi2Se2Te using ultrafast pump-probe spectroscopy. The time resolved differential reflectivity of the films exhibit fast and slow oscillations. We have given…
A striking feature of 3 dimensional (3D) topological insulators (TIs) is the theoretically expected topological magneto-electric (TME) effect, which gives rise to additional terms in Maxwell's laws of electromagnetism with an universal…
We have fabricated highly-luminescent samples with erbium-doped amorphous silicon sub-oxide (a-SiOx<Er>) layers on SiO2/Si substrates. The layers are designed to provide a resonance with large modal overlap with the active material and with…
Proximity-effect-induced superconductivity was studied in epitaxial topological insulator Bi2Se3 thin films grown on superconducting NbSe2 single crystals. A point contact spectroscopy (PCS) method was used at low temperatures down to 40…
Bismuth Selenide is a two-dimensional topological insulator material composed of stacked quintuple layers (QL). The layers are held together by a weak van der Waals force that enables surface preparation by cleaving. Low energy ion…
The binary chalcogenides Bi2Te3 and Bi2Se3 are the most widely studied topological insulators. Although the quantum anomalous Hall effect has recently been observed in magnetically doped Sb2Te3 this compound has been studied to a much…
Transient reflectivity measurements of thin films, ranging from 6 to 40 nm in thickness, of the topological insulator Bi2Se3 revealed a strong dependence of the carrier relaxation time on the film thickness. For thicker films the relaxation…
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…
A key challenge in condensed matter research is the optimization of topological insulator (TI) compounds for the study and future application of their unique surface states. Truly insulating bulk states would allow the exploitation of…
The response of thin films of Bi$_2$Se$_3$ to a strong perpendicular magnetic field is investigated by performing magnetic bandstructure calculations for a realistic multi-band tight-binding model. Several crucial features of Landau…
Insulating substrates are crucial for electrical transport study and room temperature application of topological insulator films at thickness of only several nanometers. High quality quantum well films of Bi2Se3, a typical three-dimensional…
Topological insulators (TIs) and graphene present two unique classes of materials which are characterized by spin polarized (helical) and non-polarized Dirac-cone band structures, respectively. The importance of many-body interactions that…
The physical and electronic properties of ultrathin two-dimensional (2D) layered nanomaterials are highly related to their thickness. Therefore, the rapid and accurate identification of single- and few- to multi-layer nanosheets is…
The surface states of the 3D topological insulator (TI), Bi$_2$Se$_3$, are known to host two-dimensional Dirac plasmon polaritons (DPPs) in the terahertz spectral range. In TI thin films, the DPPs excited on the top and bottom surfaces…
Understanding the interfacial electrical properties between metallic electrodes and low dimensional semiconductors is essential for both fundamental science and practical applications. Here we report the observation of thickness reduction…
We report on "graphene-like" mechanical exfoliation of single-crystal Bi2Te3 films and thermoelectric characterization of the stacks of such films. Thermal conductivity of the resulting "pseudo-superlattices" was measured by the "hot disk"…
Three-dimensional topological insulators harbour metallic surface states with exotic properties. In transport or optics, these properties are typically masked by defect-induced bulk carriers. Compensation of donors and acceptors reduces the…
The puzzling question about the floating of the topological surface state on top of a thick Pb layer, has now possibly been answered. A study of the interface made by Pb on Bi2Se3 for different temperature and adsorbate coverage condition,…
The opacity of graphene is known to be approximately given by the fine-structure constant $\alpha$ times $\pi$. We point out the fact that the opacity is roughly independent of the frequency and polarization of the light can be attributed…
Topological crystalline insulators represent a novel topological phase of matter in which the surface states are protected by discrete point group-symmetries of the underlying lattice. Rock-salt lead-tin-selenide alloy is one possible…