Related papers: Origin and evolution of surface spin current in to…
We study current carrying helical edge states in a two-dimensional topological insulator coupled to an environment of localized spins, i.e. a spin bath. The localized spins mediate elastic spin-flip scattering between the helical edge…
Dirac-like surface states on surfaces of topological insulators have a chiral spin structure that suppresses back-scattering and protects the coherence of these states in the presence of non-magnetic scatterers. In contrast, magnetic…
Topological insulators (TIs) are novel materials that manifest spin-polarized Dirac states on their surfaces or at interfaces made with conventional matter. We have measured the electron kinetics of bulk doped TI Bi$_2$Se$_3$ with angle…
We propose magnonic analogs of topological crystalline insulators which possess Dirac surface states protected by the combined symmetry of time-reversal and half translation. Constructing models of the topological magnon systems, we…
A topological insulator is a quantum material which possesses conducting surfaces and an insulating bulk. Despite extensive researches on the properties of Dirac surface states, the characteristics of bulk states have remained largely…
Discovery of topologically protected surface states, believed to be immune to weak disorder and thermal effects, opened up a new avenue to reveal exotic fundamental science and advanced technology. While time-reversal symmetry plays the key…
Longitudinal spin Seebeck effect has been investigated for an uniaxial antiferromagnetic insulator Cr2O3, characterized by a spin-flop transition under magnetic field along the c-axis. We have found that temperature gradient applied normal…
We propose a surface-edge state theory for half quantized Hall conductance of surface states in topological insulators. The gap opening of a single Dirac cone for the surface states in a weak magnetic field is demonstrated. We find a new…
Topological insulators are a new class of insulators in which a bulk gap for electronic excitations is generated by strong spin orbit coupling. These novel materials are distinguished from ordinary insulators by the presence of gapless…
Spin-momentum locking in the surface mode of topological insulators (TI) leads to the surface accumulation of spin-polarized electrons caused by bias current flows through TI samples. Here, we demonstrate that scanning tunneling microscopy…
Topological insulators are new class of materials which are characterized by a bulk band gap like ordinary band insulator but have protected conducting states on their edge or surface. These states emerge out due to the combination of…
Bias voltage dependent scattering of the topological surface state is studied by scanning tunneling microscopy/spectroscopy for a clean surface of the topological insulator Bi$_2$Te$_2$Se. A strong warping of constant energy contours in the…
We perform time- and angle-resolved photoemission spectroscopy of a prototypical topological insulator Bi$_2$Se$_3$ to study the ultrafast dynamics of surface and bulk electrons after photo-excitation. By analyzing the evolution of surface…
Majority of the A$_2$B$_3$ type chalcogenide systems with strong spin-orbit coupling, like Bi$_2$Se$_3$, Bi$_2$Te$_3$ and Sb$_2$Te$_3$ etc., are topological insulators. One important exception is Sb$_2$Se$_3$, where a topological…
Topological insulators (TIs) present a neoteric class of materials, which support delocalised, conducting surface states despite an insulating bulk. Due to their intriguing electronic properties, their optical properties have received…
The intrinsic spin Hall conductivity of typical topological insulators Sb$_2$Se$_3$, Sb$_2$Te$_3$, Bi$_2$Se$_3$, and Bi$_2$Te$_3$ in the bulk form, is calculated from first-principles by using density functional theory and the linear…
We study theoretically the surface of a topological insulator with a sliding magnetic superlattice coated above. By analyzing time-dependent Dirac equations, the dynamics of the zero mode is investigated. When the superlattice's sliding…
The surface states of three-dimensional topological insulators exhibit a helical spin texture with spin locked to momentum. To date, however, the direct all-electrical detection of the helical spin texture has remained elusive owing to the…
Magnetic oscillations of Dirac surface states of topological insulators are expected to be associated with the formation of Landau levels or the Aharonov-Bohm effect. We instead study the conductance of Dirac surface states subjected to an…
It is well established that topological insulators sustain Dirac fermion surface states as a consequence of band inversion in the bulk. These states have a helical spin polarization and a linear dispersion with large Fermi velocity. In this…