Related papers: Universal transparency and fine band structure nea…
Energy spectra both of the conduction and valence bands of the HgTe quantum wells with a width close to the Dirac point were studied experimentally. Simultaneous analysis of the Shubnikov-de Haas oscillations and Hall effect over a wide…
We describe the fine structure of Dirac states in HgTe/CdHgTe quantum wells of critical and close-to-critical thickness and demonstrate the formation of an anticrossing gap between the tips of the Dirac cones driven by interface inversion…
Quantum wells formed by layers of HgTe between Hg$_{1-x}$Cd$_x$Te barriers lead to two-dimensional (2D) topological insulators, as predicted by the BHZ model. Here, we theoretically and experimentally investigate the characteristics of…
The nature of relativistic electrons in solids depends on the precise shape of the underlying band structure. Prominently, symmetry-related mechanisms, such as the breaking of time reversal symmetry in topological insulators, can lead to…
We demonstrate that a p-n junction created electrically in HgTe quantum wells with inverted band-structure exhibits interesting intraband and interband tunneling processes. We find a perfect intraband transmission for electrons injected…
We explore the emergence of spin-polarised flat-bands at head-to-head domain walls in a recently predicted class of antiferromagnetic topological insulators hosting planar magnetisation. We show, in the framework of quantum well physics,…
The robustness of quantum edge transport in InAs/GaSb quantum wells in the presence of magnetic fields raises an issue on the fate of topological phases of matter under time-reversal symmetry breaking. A peculiar band structure evolution in…
We develop a microscopic theory of the fine structure of Dirac states in $(0lh)$-grown HgTe/CdHgTe quantum wells (QWs), where $l$ and $h$ are the Miller indices. It is shown that bulk, interface, and structure inversion asymmetry causes the…
We consider a superlattice formed by tunnel-connected identical holes, periodically placed in a two-dimensional topological insulator. We study tunneling transport through helical edges of these holes and demonstrate that the band structure…
We show that burying of the Dirac point in semiconductor-based quantum-spin-Hall systems can generate unexpected robustness of edge states to magnetic fields. A detailed ${\bf k\cdot p}$ band-structure analysis reveals that InAs/GaSb and…
Spintronic terahertz (THz) emitters have established themselves as among the most practical broadband THz sources available, yet their performance remains fundamentally limited by the spin Hall conductivity of the nonmagnetic conversion…
The two-dimensional (2D) materials are highly susceptible to the influence of their neighbors, thereby enabling the design by proximity phenomena. We reveal a remarkable terahertz (THz) spin-light interaction in 2D Dirac materials that…
We study spin-resolved resonant tunneling in a system of two quantum dots sandwiched between doped quantum wells. In the coherent (Dicke) regime, i.e., when quantum dot separation is smaller than the Fermi wavelength in a two-dimensional…
We report on terahertz (THz) electron paramagnetic resonance generalized spectroscopic ellipsometry (THz-EPR-GSE). Measurements of the field and frequency dependencies of the magnetic response due to the spin transitions associated with the…
Spin transport across interfaces is critical for spintronic devices, yet remains difficult to probe on ultrafast timescales. We use terahertz emission spectroscopy on Co|Pt heterostructures whose interface roughness is tuned through the…
We show that electrons in ordinary III-V semiconductor double wells with an in-plane modulating periodic potential and inter well spin-orbit interaction are tunable Topological Insulators (TIs). Here the essential TI ingredients, namely,…
The universal value of Faraday rotation angle close to the fine structure constant is experimentally observed in thin HgTe quantum wells with thickness on the border between trivial insulating and the topologically non-trivial Dirac phases.…
Intensive research has focused on harnessing the potential of graphene for electronic, optoelectronic, and spintronic devices by generating a bandgap at the Dirac point and enhancing the spin-orbit interaction in the graphene layer.…
Topological flat band, on which the kinetic energy of topological electrons is quenched, represents a platform for investigating the topological properties of correlated systems. Recent experimental studies on flattened electronic bands…
Spin-orbit splitting of conduction band in HgTe quantum wells was studied experimentally. In order to recognize the role of different mechanisms, we carried out detailed measurements of the Shubnikov-de Haas oscillations in gated structures…