Related papers: Abundant surface-semimetal phases in three-dimensi…
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…
Topologically trivial insulators can be classified into atomic insulators (AIs) and obstructed atomic insulators (OAIs) depending on whether the Wannier charge centers are localized or not at spatial positions occupied by atoms. An OAI can…
The anomalous surface states of symmetry protected topological (SPT) phases are usually thought to be only possible in conjunction with the higher dimensional topological bulk. However, it has recently been realized that a class of…
The surfaces of three dimensional topological insulators (3D TIs) are generally described as Dirac metals, with a single Dirac cone. It was previously believed that a gapped surface implied breaking of either time reversal $\mathcal T$ or…
The study of topological phases with unconventional bulk-boundary correspondences and nontrivial real Chern number has garnered significant attention in the topological states of matter. Using the first-principle calculations and…
Obstructed atomic phases, with their realizations in systems of diverse dimensionality, have recently arisen as one of the topological states with greatest potential to show higher-order phenomena. In this work we report a special type of…
We reveal a class of three-dimensional $d$-orbital topological materials in the antifluorite Cu$_2$S family. Derived from the unique properties of low-energy $t_{2g}$ states, their phases are solely determined by the sign of spin-orbit…
Topologically trivial insulators come in two kinds: atomic, where the Wannier charge centers (WCCs) are localized on the atoms, and obstructed atomic, where the WCCs are located away from the atoms. The latter, which can exhibit interesting…
Experimental identification of three-dimensional (3D) Dirac semimetals in solid state systems is critical for realizing exotic topological phenomena and quantum transport such as the Weyl phases, high temperature linear quantum…
According to topological quantum chemistry, a class of electronic materials have been called obstructed atomic insulators (OAIs), in which a portion of valence electrons necessarily have their centers located on some empty…
We present an ARPES study of the surface states of Ru$_2$Sn$_3$, a new type of a strong 3D topological insulator (TI). In contrast to currently known 3D TIs, which display two-dimensional Dirac cones with linear isotropic dispersions…
This work explores the topological phase diagram of inverted-band-gap semiconductors under strain and spin-orbit coupling. Using a minimalistic Luttinger Hamiltonian model, we follow the transitions between a 3D topological insulator, a…
Surface Dirac cones in three-dimensional topological insulators have generated tremendous and enduring interest for almost two decades owing to hosting a multitude of exotic properties. In this work, we unveil the existence of two types of…
Topological features of possible three-dimensional (3D) states in \alpha-type layered organic conductors are investigated within a unified framework based on Wannier charge centers (WCCs), aiming to identify their actual topological states.…
Three-dimensional higher-order topological semimetals in crystalline systems exhibit higher-order Fermi arcs on one-dimensional hinges, challenging the conventional bulk-boundary correspondence. However, the existence of higher-order Fermi…
Obstructed atomic insulator is recently proposed as an unconventional material, in which electric charge centers localized at sites away from the atoms. A half-filling surface state would emerge at specific interfaces cutting through these…
Holographic quantum matter exploits the AdS/CFT correspondence to study systems in condensed matter physics. An example of these systems are strongly correlated semimetals, which feature a rich phase diagram structure. In this work, we…
We have performed high-resolution angle-resolved photoemission spectroscopy of ternary pnictide CaAuAs which is predicted to be a three-dimensional topological Dirac semimetal (TDS). By accurately determining the bulk-band structure, we…
A 3D fermionic topological insulator has a gapless Dirac surface state protected by time-reversal symmetry and charge conservation symmetry. The surface state can be gapped by introducing ferromagnetism to break time-reversal symmetry,…
Based on the first-principles calculations, we recover the silent topological nature of Cd3As2, a well known semiconductor with high carrier mobility. We find that it is a symmetry-protected topological semimetal with a single pair of…