Topological insulators represent a novel state of matter with surface charge carriers having a massless Dirac dispersion and locked helical spin polarization. Many exciting experiments have been proposed by theory, yet their execution has been hampered by the extrinsic conductivity associated with the unavoidable presence of defects in Bi2Te3 and Bi2Se3 bulk single crystals, as well as impuriti...

The three dimensional topological insulator bismuth selenide (Bi(2)Se(3)) is expected to possess strong spin-orbit coupling and spin-textured topological surface states and, thus, exhibit a high charge to spin current conversion efficiency. We evaluate spin-orbit torques in Bi(2)Se(3)/Co(40)Fe(40)B(20) devices at different temperatures by spin torque ferromagnetic resonance measurements. As the...

Ralstonia metallidurans CH34, a soil bacterium resistant to a variety of metals, is known to reduce selenite to intracellular granules of elemental selenium (Se(0)). We have studied the kinetics of selenite (Se(IV)) and selenate (Se(VI)) accumulation and used X-ray absorption spectroscopy to identify the accumulated form of selenate, as well as possible chemical intermediates during the transfo...

In the title compund, C(21)H(33)PSe, the Se=P bond is part of a distorted tetra-hedral environment on the P atom. Both cyclo-hexyl groups adopt chair conformations. A cone angle of 170° was calculated using an adaptation of the Tolman model. Inter-molecular C-H⋯Se and C-H⋯Cg contacts are observed (Cg is the centroid of the benzene ring).

In the title compound, C(20)H(20)NPSe, the P atom lies in a distorted tetra-hedral environment. The Tolman cone angle is 157° indicating steric crowding at this atom. In the crystal, weak C-H⋯Se inter-actions create linked dimeric units and C-H⋯π inter-actions are also observed.

We present the results of an infrared spectroscopy study of topological insulators Bi(2)Se(3), Bi(2)Te(3) and Sb(2)Te(3). Reflectance spectra of all three materials look similar, with a well defined plasma edge. However, there are some important differences. Most notably, as temperature decreases the plasma edge shifts to lower frequencies in Bi(2)Se(3), whereas in Bi(2)Te(3) and Sb(2)Te(3) it ...