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Objective molecular dynamics simulations coupled with a density functional-based tight-binding model indicated that a stress-free single-walled (14,6) MoS 2 nanotube exhibits a torsional deformation of 0.87 deg/nm. Simulated electron diffraction patterns and atomic-resolution annular dark field scanning transmission electron microscopy (ADF-STEM) images of(More)
Three-dimensional (3D) topological insulators are known for their strong spin-orbit coupling (SOC) and the existence of spin-textured surface states that might be potentially exploited for "topological spintronics." Here, we use spin pumping and the inverse spin Hall effect to demonstrate successful spin injection at room temperature from a metallic(More)
The interaction of H atoms with the curved concentric graphene walls of a multiwall carbon nanotube and the stacked planar graphene sheets of graphite was investigated using a combination of high resolution transmission electron microscopy ͑HRTEM͒ in conjunction with electron energy-loss and Raman spectroscopies. Continuous cylindrical graphene walls of a(More)
The electronic structure of wurtzite InN has been investigated by electron energy loss spectroscopy ͑EELS͒. Spectra of the nitrogen K edge and the indium M 4,5 edge have been measured and were compared with calculated partial, N 2p and In 5p conduction band density of states in InN. Excellent agreement on the relative positions of the characteristic peaks(More)
A semiquantitative correlation between experimental observations and theoretical prediction in electron microscopy is achieved. Experiments conducted on amorphous silicon in the convergent beam electron diffraction mode provide measurements of the reduction of the central-disk intensity. In addition to elastic scattering the effects of multiple inelastic(More)
Internal crystalline structure of cementite catalyst particles located inside the base of mul-tiwall carbon nanotubes was studied using nanoprobe convergent-beam electron diffrac-tion. The catalyst particles are single crystalline but exhibit combinations of small-angle ($1°–3°) rotations, twists, and bends along their axial length between adjacent(More)
We examined the structure, morphology, and orientation of catalyst nanoparticles used for seeding and growing multiwall carbon nanotubes (MWCNTs) by plasma enhanced chemical vapor deposition in CH4/H2 gas mixtures. Iron catalyst nanocrystals are converted to Fe3C in CH4/H2 plasmas and the MWCNTs grow from Fe3C nanocrystals. Initially faceted and equiaxed(More)
Localized surface plasmon resonances (LSPRs) enable tailoring of the optical response of nanomaterials through their free carrier concentration, morphology, and dielectric environment. Recent efforts to expand the spectral range of usable LSPR frequencies into the infrared successfully demonstrated LSPRs in doped semiconductor nanocrystals. Despite(More)
Annular dark field scanning transmission electron microscope (ADF-STEM) images allow detection of individual dopant atoms located on the surface of or inside a crystal. Contrast between intensities of an atomic column containing a dopant atom and a pure atomic column in ADF-STEM image depends strongly on specimen parameters and microscope conditions.(More)