Related papers: Observation of robust one-dimensional edge channel…
Topological states of matter are robust quantum phases, characterised by propagating or localised edge states in an insulating bulk. Topological boundary states can be triggered by various mechanisms, for example by strong spin-orbit…
Low-dimensional electronic systems have traditionally been obtained by electrostatically confining electrons, either in heterostructures or in intrinsically nanoscale materials such as single molecules, nanowires, and graphene. Recently, a…
Quantum spin Hall insulators (QSHIs) and excitonic insulators (EIs) are prototypical topological and correlated states of matter, respectively. The topological phase transition between the two has attracted much theoretical interest but…
Quantum spin Hall (QSH) effect is promising for achieving dissipationless transport devices due to the robust gapless states inside insulating bulk gap. Here, by using first-principles calculations, we discover group-IV chalcogenide Si2Te2…
Quadrupole topological insulators are a new class of topological insulators with quantized quadrupole moments, which support protected gapless corner states. The experimental demonstrations of quadrupole-topological insulators were reported…
The exploration of topological phases remains a cutting-edge research frontier, driven by their promising potential for next-generation electronic and quantum technologies. In this work, we employ first-principles calculations and…
A Kramers pair of helical edge states in quantum spin Hall effect (QSHE) is robust against normal dephasing but not robust to spin dephasing. In our work, we provide an effective spin dephasing mechanism in the puddles of two-dimensional…
Quantum spin Hall insulators, or synonymously known as 2D topological insulators, are crucial 2D systems hosting topologically protected edge states. The working temperature of this topological quantum phase is dictated by the inverted…
The discovery of the Quantum Spin Hall state, and topological insulators in general, has sparked strong experimental efforts. Transport studies of the Quantum Spin Hall state confirmed the presence of edge states, showed ballistic edge…
Two-dimensional (2D) topological insulators (TIs), a new state of quantum matter, are promising for achieving the low-power-consuming electronic devices owning to the remarkable robustness of their conducting edge states against…
We report the experimental observation of Anderson localization in two-dimensional (2D) electrons and holes in the bulk of HgTe quantum wells with a semimetallic spectrum and under strong disorder. In contrast, the one-dimensional (1D) edge…
Although many possible two-dimensional (2D) topological insulators (TIs) have been predicted in recent years, there is still lack of experimentally realizable 2D TI. Through first-principles and tight-binding simulations, we found an…
Recently, higher-order topological insulators have been attracting extensive interest. Unlike the conventional topological insulators that demand bulk gap closings at transition points, the higher-order band topology can be changed without…
Spin-polarized conducting edge currents counterpropagate in quantum spin Hall (QSH) insulators and are protected against disorder-driven localizations by the time-reversal symmetry. Using these spin-currents for device applications require…
The notion of topological insulators (TIs), characterized by an insulating bulk and conducting topological surface states, can be extended to higher-order topological insulators (HOTIs) hosting gapless modes localized at the boundaries of…
The boundary modes of topological insulators are protected by the symmetries of the non-trivial bulk electronic states. Unless these symmetries are broken, they can give rise to novel phenomena, such as the quantum spin Hall effect in…
Recently, the theory of quantized dipole polarization has been extended to account for electric multipole moments, giving rise to the discovery of multipole topological insulators (TIs). Both two-dimensional (2D) quadrupole and…
Three-dimensional (3D) topological ferroelectric (FE) insulators, in which topological and FE orders naturally coexist, enable field-controlled spintronic devices. In this work, we predict a new structure of bismuth monohalides Bi4Br4 and…
In $strong$ topological insulators protected surface states are always manifest, while in $weak$ topological insulators (WTI) the corresponding metallic surface states are either manifest or hidden, depending on the orientation of the…
Recently, the quantum spin-Hall edge channels of two-dimensional colloidal nanocrystals of the topological insulator Bi$_2$Se$_3$ were observed directly. Motivated by this development, we reconsider the four-band effective model which has…