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The topology of the electron wavefunctions in certain band insulators can give rise to novel topological phases. Materials harbouring such topological phases are termed topological insulators (TI). A gapped bulk electronic spectrum, described by a topologi ...
The prospect of optically inducing and controlling a spin-polarized current in spintronic devices has generated wide interest in the out-of-equilibrium electronic and spin structure of topological insulators. In this Letter we show that only measuring the ...
Tellurium is the only element which forms a variety of minerals with gold as principal component (e.g. calaverite AuTe2, krennerite (AuAg)Te2, petzite Ag3AuTe2 and sylvanite AgAuTe4). These minerals have been known for a long time and are of economic value ...
Despite the close association between tellurium (Te) and gold (Au) in many epithermal, orogenic, and intrusion-related hydrothermal ore deposits, the hydrothermal chemistry of Te remains poorly understood. We studied the protonation/ deprotonation and stru ...
Elsevier2013
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Phonon dynamics in Bi, Bi2Se2, and CuxBi2Se3 (x=0, 0.1, 0.125) single crystals was investigated using femtosecond pump-probe spectroscopy. Two damped oscillations in measured transient reflectivity changes were observed, respectively, attributed to coheren ...
Thermal transport is a key feature for the operation of phase change memory devices which rest on a fast and reversible transformation between the crystalline and amorphous phases of chalcogenide alloys upon Joule heating. In this paper we report on the ab ...
A commercial scanning thermal microscope has been upgraded to facilitate its use in estimating the radial thermal diffusivity of thin films close to room temperature. The modified setup includes a microcontroller driven microhotplate coupled with a Bluetoo ...
Electrodeposited bismuth telluride (Bi2Te3) nanowires using anodic alumina (AAO) templates show anisotropic thermal properties in a direction parallel and perpendicular to the nanowire/nanochannel axis. The present study reports thermal diffusivity measure ...
Elsevier Science Bv2014
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Two new isostructural layered oxohalides FeTe3O7X (X = Cl, Br) were synthesized by chemical vapor transport reactions, and their crystal structures and magnetic properties were characterized by single-crystal X-ray diffraction, Raman spectroscopy, magnetic ...
2011
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The application of pressure to elemental bismuth reduces its conduction-valence band overlap, and results in a semimetal-semiconductor (SMSC) transition around 25 kbar. This transition is nominally of the topological "Lifshitz'' Fermi surface variety, but ...