Related papers: Highly Tunable Band Inversion in AB2X4 (A=Ge, Sn, …

Employing ab initio electronic calculations, we propose a new type of two-dimensional (2D) topological insulator (TI), monolayer (ML) low buckled (LB) mercury telluride (HgTe) and mercury selenide (HgSe), with tunable band gaps. Monolayer…

In a topological crystalline insulator (TCI) the inversion of the bulk valence and conduction bands is a necessary condition to observe surface metallic states. Solid solutions of Pb$_{1-x}$Sn$_x$Te have been shown to be TCI, where band…

We numerically investigate and experimentally demonstrate an in-situ topological band transition in a highly tunable mechanical system made of cylindrical granular particles. This system allows us to tune its inter-particle stiffness in a…

A topological insulator possesses a bulk energy gap splitting the lowest empty band from the highest occupied electronic band. The electronic states at the surface (or edge in two dimensions), on the other hand, of a topological insulator…

In typical topological insulator (TI) systems the TI is bordered by a non-TI insulator, and the surrounding conventional insulators, including vacuum, are not generally treated as part of the TI system. Here, we implement the first material…

The characteristics of topological insulators are manifested in both their surface and bulk properties, but the latter remain to be explored. Here we report bulk signatures of pressure-induced band inversion and topological phase…

FeTe$_{0.55}$Se$_{0.45}$(FTS) occupies a special spot in modern condensed matter physics at the intersections of electron correlation, topology, and unconventional superconductivity. The bulk electronic structure of FTS is predicted to be…

By combining transport and photo emission measurements on (Bi1-xInx)2Se3 thin films, we report that this system transforms from a topologically non-trivial metal into a topologically trivial band insulator through three quantum phase…

Van de Waals heterostructures (VDWH) is an emerging strategy to engineer the electronic properties of two-dimensional (2D) material systems. Motivated by the recent discovery of MoSi$_2$N$_4$ - a synthetic septuple-layered 2D semiconductor…

The phase transition from a topological insulator to a trivial band insulator is studied by angle-resoled photoemission spectroscopy on Bi$_{2-x}$In$_{x}$Se$_{3}$ single crystals. We first report the complete evolution of the bulk band…

The electronic structure of semiconducting 2D materials such as transition metal dichalcogenides (TMDs) is known to be tunable by its environment, from simple external fields applied with electrical contacts up to complex van der Waals…

Tin Selenide (SnSe) is one of the best thermoelectric materials reported to date. The possibility of growing few-layer SnSe helped boost the interest in this long-known, earth abundant material. Pristine SnSe in bulk, mono- and few-layer…

Recently the Quantum Spin Hall effect (QSH) was theoretically predicted and experimentally realized in a quantum wells based on binary semiconductor HgTe[1-3]. QSH state and topological insulators are the new states of quantum matter…

Theoretical simulation to phase change materials such as Ge-Sb-Te has suffered from two methodology issues. On the one hand, there is a lack of efficient band gap correction method for density functional theory, which is suitable for these…

The recently discovered three dimensional or bulk topological insulators are expected to exhibit exotic quantum phenomena. It is believed that a trivial insulator can be twisted into a topological state by modulating the spin-orbit…

Topological physics and strong electron-electron correlations in quantum materials are typically studied independently. However, there have been rapid recent developments in quantum materials in which topological phase transitions emerge…

Topological insulators (TIs) have been found in strained binary HgTe and ternary I-III-VI2 chalcopyrite compounds such as CuTlSe2 which have inverted band structures. However, the non-trivial band gaps of these existing binary and ternary…

We propose SnBi2Te4 to be a novel candidate material exhibiting temperature (T) mediated transitions between rich topological phases. From a combined theoretical and experimental studies, we find that SnBi2Te4 goes from a low-T topological…

The combination of magnetism and topological properties in one material platform is attracting significant attention due to the potential of realizing low power consumption and error-robust electronic devices. Common practice is to start…

An effective tight-binding (TB) Hamiltonian for monolayer GeSnH$_2$ is proposed which has an inversion-asymmetric honeycomb structure. The low-energy band structure of our TB model agrees very well with previous {\it ab initio} calculations…