Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Two tetranuclear manganese(II) complexes [Mn(II)4(thiaS)2] (1) and [Mn(II)4(thiaSO)2] (2) have been synthesized under solvothermal conditions in methanol with p-tert-butylthiacalix[4]arene (thiaS) and p-tert-butylsulfinylthiacalix[4]arene (thiaSO). For both complexes, the structure has been established from single-cry…
The effects of B and P codoping on the impurity formation energies and electronic properties of Si nanocrystals (Si-nc) are calculated by a first-principles method. We show that, if carriers in the Si-nc are perfectly compensated by simultaneous doping with n- and p-type impurities, the Si-nc undergo a minor structura…
A novel method of making silver nanoparticles in water-in-oil microemulsions using the surfactants as both the reducing agent and as the structure-directing agent is presented. Since no external strong reducing agent is used the kinetics of the formation is slow, which makes it possible to study the silver nanoparticl…
We present data for the time dependence of wooden spheres penetrating into a loose noncohesive packing of glass beads. The stopping time is a factor of 3 longer than the time d/v0 needed to travel the total penetration distance d at the impact speed v0. The acceleration decreases monotonically throughout the impact. T…
We investigate the temperature dependency of the elastic constants of polyelectrolyte multilayers made from poly(diallyldimethylammonium chloride) (PDADMAC) and poly(styrenesulfonate) (PSS) by measuring the stiffness of individual hollow polyelectrolyte multilayer capsules in water using AFM force spectroscopy. Statis…
Abstract In the bulk, at equilibrium, diblock copolymers microphase separated into nanoscopic morphologies ranging from body‐centered cubic arrays of spheres to hexagonally packed cylinders to alternating lamellae, depending on the volume fraction of the components. However, when the block copolymers are forced into c…
In RBaCo2O(5+x) compounds (R is rare earth), the variability of the oxygen content allows precise doping of CoO2 planes with both types of charge carriers. We study transport properties of doped GdBaCo2O(5+x) single crystals and find a remarkable asymmetry in the behavior of holes and electrons doped into a parent ins…
In this work, we report on the epitaxial growth of multiferroic YMnO3 on GaN. Both materials are hexagonal with a nominal lattice mismatch of 4%, yet x-ray diffraction reveals an unexpected 30° rotation between the unit cells of YMnO3 and GaN that results in a much larger lattice mismatch (10%) compared to the unrotat…
We report an alternative procedure to incorporate gold nanoparticles into 3D ordered colloidal crystal film. The size of gold nanoparticles within the films can be controlled from about 10 nm to about 60 nm by simply varying the gold plating time. The application of the as-prepared films in surface-enhanced Raman spec…
Current-driven magnetization switching in low-resistance Co40Fe40B20/MgO/Co40Fe40B20 magnetic tunnel junctions (MTJs) is reported. The critical-current densities Jc required for current-driven switching in samples annealed at 270C and 300C are found to be as low as 7.8 x 10^5 A/cm^2 and 8.8 x 10^5 A/cm^2 with accompan…
The highest superconducting temperature T$_c$ observed in any elemental metal (Li with T$_c$ ~ 20 K at pressure P ~ 40 GPa) is shown to arise from critical (formally divergent) electron-phonon coupling to the transverse T$_1$ phonon branch along intersections of Kohn anomaly surfaces with the Fermi surface. First prin…
We investigated dependence of tunnel magnetoresistance effect in CoFeB/MgO/CoFeB magnetic tunnel junctions on Ar pressure during MgO-barrier sputtering. Sputter deposition of MgO-barrier at high Ar pressure of 10 mTorr resulted in smooth surface and highly (001) oriented MgO. Using this MgO as a tunnel barrier, tunnel…
We study the carrier capture and relaxation due to Coulomb scattering in nitride-based quantum dots on the basis of population kinetics. For the states involved in the scattering processes the combined influence of the quantum-confined Stark effect and many-body renormalizations is taken into account. The charge separ…
Zinc oxide crystals grown by the seeded chemical vapor transport method have been annealed in zinc vapor at 1100 °C for 30 min. These thermochemical reduction treatments produce a deep red coloration in the crystals and increase their n-type electrical conductivity. Electron paramagnetic resonance (EPR), optical absor…
Colloidal nanoparticles may possess many functional properties, whose nature may be electronic, chemical, biological, mechanical, . It is often advantageous to incorporate them into a matrix material, , a polymer solution or melt, or an elastomer, in order to obtain a 'nanomaterial' with additional properties brought…
An investigation is made into whether the reaction rate formalism also applies to describing inelastic tunneling vibronic processes associated with the absorption and emission of phonons. We propose that Bardeen-Christov's quantum-mechanical approach to the transition (tunneling) probabilities originally intended for…
Electron dynamics in metallic clusters are examined using a time-dependent density functional theory that in-cludes a "memory term", i.e. attempts to describe temporal non-local correlations. Using the Iwamoto, Gross and Kohn exchange-correlation (XC) kernel we construct a translationally invariant memory action from…
Ever since high Tc superconductivity was discovered in La-based mixed oxide system by Bednorz and Muller, enormous efforts have been put in by several researchers around the world in understanding the origin and mechanism of superconductivity in these, as well as in systems derived from them. It is a proven fact that…
The doped perovskite cobaltite ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CoO}}_{3}$ (LSCO) has been advanced as a model system for studying intrinsic magnetic phase separation. We have employed a first-order reversal curve (FORC) method to probe the amount of irreversible switching in bulk polycrystal…
High-quality CdSxSe1-x nanobelts of variable composition (0 </= x </= 1) were fabricated by a simple one-step thermal evaporation route. Photoluminescence measurements showed that all the CdSxSe1-x nanobelts have a single near-bandedge emission band, and their spectral maximum positions can be tuned from approximately…