相关论文: Bulk and surface electronic structure of the dual-…
We performed high-resolution spin- and angle-resolved photoemission spectroscopy studies of the electronic structure and the spin texture on the surface of Bi$_2$Se$_3$, a model topological insulator. By tuning the photon energy, we found…
We present angle resolved photoemission spectroscopy measurements of the surface states on in-situ grown (111) oriented films of Pb$_{1-x}$Sn$_{x}$Se, a three dimensional topological crystalline insulator. We observe surface states with…
Defect-free SrTiO3 (STO) is a band insulator but Angle Resolved Photoemission Spectroscopy (ARPES) experiments have demonstrated the existence of a nanometer thin two-dimensional electron liquid (2DEG) at the (001) oriented surface of this…
Topological insulators are bulk semiconductors that manifest in-gap massless Dirac surface states due to the topological bulk-boundary correspondence principle [1-3]. These surface states have been a subject of tremendous ongoing interest,…
The band inversion in topological phase matters bring exotic physical properties such as the emergence of a topologically protected surface states. They strongly influence the surface electronic structures of the investigated materials and…
Two quintuple layers of strong topological insulator Bi2Se3 are coupled by a Bi bilayer in BiSe crystal. We investigated its electronic structure using angle resolved photoelectron spectroscopy to study its topological nature. Dirac like…
Saddle-point van Hove singularities in the topological surface states are interesting because they can provide a new pathway for accessing exotic correlated phenomena in topological materials. Here, based on first-principles calculations…
PtBi2 with a layered trigonal crystal structure was recently reported to exhibit an unconventional large linear magnetoresistance, while the mechanism involved is still elusive. Using high resolution angle-resolved photoemission…
Recently, crystalline-symmetry-protected three-dimensional (3D) bulk Dirac semimetal phase has been experimentally identified in a stoichiometric high-mobility compound, Cd3As2. The Dirac state observed in Cd3As2 has been attributed to…
Bi2Te3 is a member of a new class of materials known as topological insulators which are supposed to be insulating in the bulk and conducting on the surface. However experimental verification of the surface states has been difficult in…
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…
Symmetry plays a major role in all disciplines of physics. Within the field of topological materials there is a great interest in understanding how the mechanics of crystalline and internal symmetries protect crossings between the…
We investigate systematically the bulk and surface electronic structure of the candidate nodal-line semimetal CaAgAs by angle resolved photoemission spectroscopy and density functional calculations. We observed a metallic, linear,…
High resolution angle-resolved photoemission measurements have been carried out on transition metal dichalcogenide PdTe2 that is a superconductor with a Tc at 1.7 K. Combined with theoretical calculations, we have discovered for the first…
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…
We construct two-band topological semimetals in four dimensions using the unstable homotopy of maps from the three-torus $T^3$ (Brillouin zone of a 3D crystal) to the two-sphere $S^2$. Dubbed ``Hopf semimetals'', these gapless phases…
Topological superconductors host new states of quantum matter which show a pairing gap in the bulk and gapless surface states providing a platform to realize Majorana fermions. Recently, alkaline-earth metal Sr intercalated Bi2Se3 has been…
We present the theory describing the various surface electronic states arisen from the mixing of conduction and valence bands in a strained mercury telluride (HgTe) bulk material. We demonstrate that the strain-induced band gap in the…
While evidence of a topologically nontrivial surface state has been identified in surface-sensitive measurements of Bi2Se3, a significant experimental concern is that no signatures have been observed in bulk transport. In a search for such…
The three-dimensional topological semimetals represent a new quantum state of matter. Distinct from the surface state in the topological insulators that exhibits linear dispersion in two-dimensional momentum plane, the three-dimensional…