The Avrami's kinetics was known to be the best theory to describe Bi-2223 crystals growth. Whereas, it cannot explain the fact that maximum product volume appearing at optimum sintering time during synthesis Bi-22...
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We report the enhanced interface properties between passivation layers and InSb by using remote PECVD system. SiO2 and Si3N4 layers deposited by remote PECVD showed lower interface trap densities than layers deposited...
We report the enhanced interface properties between passivation layers and InSb by using remote PECVD system. SiO2 and Si3N4 layers deposited by remote PECVD showed lower interface trap densities than layers deposited by normal PECVD. SiO2 layers deposited by remote PECVD showed 7.1×1011 cm−2 eV−1 of interface trap density at midgap which is slightly lower than SiO2 layers deposited by PECVD. Si3N4 layers deposited by remote PECVD showed 1.6∼1.7×1012 cm−2 eV−1 at midgap which is 3 times lower than Si3N4 layers deposited by PECVD. Interface properties of SiO2 are superior to that of Si3N4 in both case of PECVD and remote PECVD. To investigate the interface properties between SiO2 and InSb, X‐ray photoelectron spectroscopy was conducted. Indium and antimony oxide phases were found at the interface and these oxide phases could act as the origin of interface traps.
We report systematic ab initio calculations of the electronic band structure, phonon dispersion relation, and the structural characterization of FeF2 in the rutile (P42/mnm) structure as well as in several high-pressu...
We report systematic ab initio calculations of the electronic band structure, phonon dispersion relation, and the structural characterization of FeF2 in the rutile (P42/mnm) structure as well as in several high-pressure phases by means of the generalized gradient approximation (GGA)+U approximation. Using the phonon dispersion relations, we calculated the Gibbs free energy and evaluated the phase transitions at 300 K, at which most experimental measurements are performed. Calculated Raman and infrared vibrational modes, lattice parameters, and electronic structure for all considered crystalline structures are compared with available experimental data. Our calculations show that at 5.33 GPa, the FeF2 undergoes a second-order proper ferroelastic phase transition, rutile → CaCl2-type structure. This result is supported by the softening of the elastic shear module Cs in the rutile phase, the softening (hardening) of the B1g (Ag) Raman active mode in the rutile (CaCl2-type) structure near the transition pressure, and the decrease of the square of the spontaneous strain ess from the CaCl2-type structure. This demonstrates that the rutile → CaCl2-type phase transition is driven by the coupling between the Raman active B1g mode and shear modulus Cs. At 8.22 GPa, the CaCl2-type structure undergoes a first-order phase transition to the Pbca phase, a distorted fcc Pa3¯ phase with a volume reduction of ΔV≈7%, as reported in experiments. Upon further increase of the pressure, the Pbca phase transforms to a Fmmm phase othorhombic center-type structure at ∼20.38 GPa, with ΔV≈2.5%. Finally, at 25.05 GPa, there is a phase transition to the orthorhombic cotunnite structure (Pnma space group), with ΔV≈5.8%, which is stable up to 45 GPa, the largest considered pressure. The coordination number for the Fe ion in each phase is 6, 6, 6, 8, and 9 for rutile, CaCl2-type, Pbca, Fmmm, and cotunnite structures, respectively. The evolution of the band gap, phonon frequencies, and magnetic momen
The emergence of Fano resonances in the extinction spectra of arrays of aluminum nanodiscs 30-200 nm in diameter deposited on [Zn, Mg]O quantum wells provide the first evidence of strong coupling in zinc oxide heteros...
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Cells offer natural examples of highly efficient networks of nanomachines. Accordingly, both intracellular and intercellular communication mechanisms in nature are looked to as a source of inspiration and instruction ...
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A process, continuous wrapping tantalum barrier, has been developed and investigated in order to reduce the manufacturing cost. By avoiding inserting expensive tantalum tube, a long sheet barrier was directly used to ...
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Soft and high magnetic moment Co37Fe63 films were electro-deposited with variable additives on Cu/Ti/Si substrates. The correlation between structure and magnetic properties has been investigated. TEM showed the cryst...
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ISBN:
(纸本)9781118029473
Soft and high magnetic moment Co37Fe63 films were electro-deposited with variable additives on Cu/Ti/Si substrates. The correlation between structure and magnetic properties has been investigated. TEM showed the crystal structure of the films to be BCC with a 〈111〉 texture, and a grain size in the range of 10-20 nm. Oxygen in the deposited films has been identified by EDS and EELS using HAADF STEM. SIMS analysis revealed the presence of hydrogen and oxygen in the deposited CoFe films. Electron microscopy results showed that the oxygen was mainly distributed along the grain boundaries in the CoFe film. In regions where oxygen was present in the films, the Fe content was enhanced relative to Co. The magnetic properties of the deposits have been measured by Vibrating Sample Magnetometer (VSM), quantifying the impact of incorporated oxygen in the film on the saturation magnetization and the coercivity.
Because of their luminescent properties, phosphors make excellent candidates for radiation detectors. The materials are inclined to luminesce when exposed to a variety of radiation sources including gammas, protons, a...
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Because of their luminescent properties, phosphors make excellent candidates for radiation detectors. The materials are inclined to luminesce when exposed to a variety of radiation sources including gammas, protons, alphas and so forth. However, the vast majority of research and use of phosphors as radiation sensors are as scintillators-when luminescence spontaneously occurs due to the incident radiation. In this case, incident radiation promotes electrons to excited levels. The excited electrons subsequently decay to produce photons that can be detected. The luminescence is therefore a result of ionizing radiation.
We demonstrate the resonance wavelength and quality factor dependence of 50nm defect-hole placement within photonic crystal L3 microcavities. Proper placement of defect-holes leads to a 12% increase in photonic crysta...
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