Fig. 1.Schematic representation of the surface energy levels of a crystal as a function of surface crystal momentum. (A) Band structure for a conventional insulator. (B) Band structure for a topological insulator. Theshaded regionsshow the bulk continuum states, whereas thegreen and red linesdep...
Time reversal switches both the direction of “quantum spin Hall effect state” or 2D topological insulator contains left-moving and right- propagation and the spin direction, interchanging the moving modes that have opposite spin and are related by time-reversal symmetry. This edge two counter-...
direct writing method, as shown in Fig.19. This progress culminated in numerous milestones in topological insulators such as the Anderson insulator14, fractal photonic topological insulator15,16, and bimorphic Floquet topological insulator17. Most recently, a significant advancement was made by introduci...
The magnetoresistance studies show a quasi-2D linear magnetoresistance at high temperature region, which is probably caused by surface accumulation layer and is different from others' works observed in topological insulator which are attributed to the gapless linear energy dispersion. In addition, an ...
2c. When d2/d1≥1.2, the system is topologically non-trivial and can support second-order topological corner states. The system is trivial without any topological edge modes if d1/d2≥1.2. Here, the trivial phase is the gapped (insulator) state, the metallic/conducting phase represents ...
By definition, a topological insulator (TI) is recognized by the observation of bulk insulating state and Dirac surface state in quantum materials; which inherently is insusceptible to external defects scattering on account of the protection of time reversal symmetry (TRS).[1], [2], [3], [4...
Pressure-induced superconductivity in the Zintl topological insulator SrIn 2 As 2 The Zintl compound AIn2X2 (A = Ca, Sr, and X = P, As), as a theoretically predicted nonmagnetic topological insulator, requires experiments to understand i... W Cao,H Yang,Li, YongkaiPei, CuiyingWang, Qi...
To understand the essence of topological transport, it is instructive to recall the first topological insulator ever discovered: the integer quantum Hall effect [2]. This phenomenon occurs in semiconductors under low temperature and a strong magnetic field (Figure 1b). The Lorentz force opens a ba...
It represents a spin liquid-like phase where the charge is stripped from the original electrons and frozen in a Mott insulating phase; the spinons (i.e., the electrons' spin degree of freedom), however, inherit the non-trivial band topology of the topological insulator and provide spin-only...
Analogue quantum Hall effect and quantum spin Hall effect The QHE provided the first example of the topological phases of matter. Observing the QHE, a 2D sample subjected to low temperature and a strong magnetic field exhibited the behavior of an insulator in the bulk and a metal along the ed...