We performed high-resolution spin- and angle-resolved photoemission spectroscopy studies of the electronic structure and the spin texture on the surface of Bi2Se3, a model TI. By tuning the photon energy, we found that the topological surface state is well separated from the bulk states in the vicinity of kz = Z plane of the bulk Brillouin zone. The spin-resolved measurements in that region ind...

If the pathological left-handedness theory is valid, left-handed people who also experienced pregnancy and birth stress events (PBSEs) would especially be expected to deviate from the cognitive norm (rather than left-handers in general). This hypothesis was tested in a large sample of healthy children (aged 6.6-15.9 years). Multiple cognitive abilities were assessed, including verbal fluency an...

The pressure-induced superconductivity and structural evolution of Bi2Se3 single crystals are studied. The emergence of superconductivity at an onset transition temperature (Tc) of about 4.4 K is observed at around 12 GPa. Tc increases rapidly to a maximum of 8.2 K at 17.2 GPa, decreases to around 6.5 K at 23 GPa, and then remains almost constant with further increases in pressure. Variations i...

We study the low-temperature transport properties of Bi2Se3 thin films grown by magnetron sputtering. A positive magnetoresistance resulting from the weak antilocalization (WAL) effect is observed at low temperatures. The observed WAL effect is two dimensional in nature. Applying the Hikami-Larkin-Nagaoka theory, we have obtained the dephasing length. It is found that the temperature dependence...

We investigate the band dispersion and the spin texture of topologically protected surface states in the bulk topological insulators Bi2Se3 and Bi2Te3 by first-principles methods. Strong spin-orbit entanglement in these materials reduces the spin polarization of the surface states to ∼50% in both cases; this reduction is absent in simple models but of important implications to essentially any s...

The first production of weakly agglomerated zinc selenide nanopowders by evaporation a target the required chemical composition in argon using fiber ytterbium laser is reported. Nanoparticles have shape polyhedrons and, more rarely, spheres with an average size 18 nm. According to XRD data, obtained contain two phases: stable cubic phase (sphalerite, 40 wt.%) and metastable hexagonal (wurtzite,...

Lead selenide (PbSe) emerged 70+ years ago for its unique photoconductive sensitivity to the mid-wave infrared (MWIR) spectrum; however, new and exciting research continues ignite interest in this material day.

We report an in-plane optical spectroscopy study on the newly discovered iron-selenide superconductor K0.75Fe1.75Se2. The measurement revealed the development of a sharp reflectance edge at very low frequency below Tc on the relatively incoherent electronic background. The phenomenon was explained as arising from the Josephson-coupling plasmon of superconducting condensate. Together with the tr...

The electrochemical cell: Se|TGSesingle crystal|Se, with tri-glycine selenide as solid electrolyte was employed to observe the ferroelectric-paraelectric phase transition. The charge, which normally occurs on the surface of the ferroelectric crystal in the polar phase, is thus incorporated in the electrical double layer of the cell and can be precisely monitored. The pyroelectric currents can a...

Chromium- and cobalt-doped zinc selenide nanoparticles were synthesized using a low-temperature reactive solution growth method. The morphological optical characteristics compared to those of doped (ZnSe) bulk crystals grown by the physical vapor transport (PVT) We observed agglomeration particles; however, thioglycerol capping agent has been shown limit particle grain agglomeration. This proce...