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A parametric approximation approach is proposed to study the electronic transport properties in quantum transport systems such as quantum dots and molecules. This approach is developed from the nonequilibrium Green function technique and employs an approximate nonself-consistent (NSC) procedure to substitute the original self-consistent (SC) one when the many-body term, such as electron–electron interaction, is considered. A simple model of one eigen-energy level coupled to two continuous energy spectrums is used to illustrate the new NSC method that can be generalized to multi-energy level cases in a straightforward manner. The comparison between the NSC results with the SC results demonstrate the correctness and the effectiveness of the new method. [ABSTRACT FROM AUTHOR]

Growth mechanisms and defects formation of the manganese mercury thiocyanate (MMTC) crystal have been investigated by atomic force microscopy (AFM). Both screw dislocation controlled growth and 2D nucleation growth occur on the {110} faces. Stacking faults are observed among dislocation hillocks and the formation of them probably results from the different crystallization orientations of different spirals. Hollow channels are found around the nucleation islands and the formation of them is due to the instability of the interface generated by the rapid nucleation and growth speeds. [ABSTRACT FROM AUTHOR]

As the carbon nanotubes (CNTs) films are applied to the field emission cathodes in the vacuum devices, heat treatment in the range of 400°C–500°C is often conducted during the device sealing process, especially for glass-based devices. The annealing temperature effect on the field emission of the CNT films prepared by chemical vapor deposition is investigated. The CNT film annealed at 400°C in air contains less amorphous carbon phase, and shows better field emission properties comparing to the as-grown CNT film. Annealing at 450°C causes serious oxidative damage along the tube walls, resulting in the poor field emission performance. The CNTs annealed at 500°C are all burned out. The experiment shows that the sealing temperature at 400°C or below can be conducted in air, while the sealing temperature above 400°C should be done in N2 or Ar ambient. [ABSTRACT FROM AUTHOR]

Our current understanding of routes to chaos is mainly based on torus bifurcation where new periods are generated, the period-doubling mechanism revealed in the logistic map, and intermittency where periodic and burst motion appear alternatively. We present a possible new route to chaos based on our geometric picture of the frequency-locking of limit-cycles in semiconductor superlattices. In the period-double route and/or its variations, the period increases exponentially with bifurcation order, whereas the period in the new route increases linearly with the order of bifurcations. [ABSTRACT FROM AUTHOR]

Single crystals of nonlinear optical material, L-arginine trifluoroacetate (abbreviated as LATF), were grown from an aqueous solution by the low temperature solution growth method. The cell parameters of the grown crystal were determined by the X-ray powder diffraction analysis. Atomic force microscopy (AFM) was used to investigate the surface morphology of {101} cleavage faces of LATF. Straight steps and two-dimensional nuclei were observed. Liquid inclusions and impurities as defects for revealing macrosteps were demonstrated. The molecular structure and crystal structure correlative with surface morphology were discussed. [ABSTRACT FROM AUTHOR]

We explore the nature of the σ or f0(600) meson using large Nc technique, assuming that the σ pole dominates low energy physics in the IJ=00 channel. We trace the Nc dependence of the σ pole position using [1,1] Padé approximation of SU(3) chiral amplitude, [1,2] Padé approximation of SU(2) chiral amplitudes, and the PKU parametrization form. We find that in all 3 cases the σ pole moves to the real axis of the complex s-plane. Finally we construct a pedagogical example using the SU(2) Padé amplitude to show that when the analyticity property of the scattering amplitude is violated, it is possible that the σ pole resides on the complex s plane when Nc is large. [ABSTRACT FROM AUTHOR]

We study the entanglement in the three-site Heisenberg XY model with nonuniform external magnetic fields and obtain analytic expressions for the measures of entanglement in the system with both the periodic and the open boundary conditions. We show that both the ground state and the excited states of the system possess remarkable entanglement properties and the entanglement clearly depends on the magnitude of external fields. We obtain the pairwise thermal entanglement of the system. We also discuss the boundary effects on the entanglement. [ABSTRACT FROM AUTHOR]

Efficient hydrogenated diamond-like carbon (DLC) film deposition in a plasma reactor that features both the capacitive and inductively coupled operation regimes is reported. The hydrogenated DLC films have been prepared on silicon wafers using a low-frequency (500 kHz) inductively coupled plasma (LF ICP) chemical vapor deposition (CVD) system. At low RF powers, the system operates as an asymmetric capacitively coupled plasma source, and the film deposition process is undertaken in the electrostatic (E) discharge regime. The films deposited in the electrostatic mode feature graphite-like structure. Above the mode transition threshold, the high-density inductively coupled plasma is produced in the electromagnetic (H) discharge regime. Raman spectrometry suggests the possibility to control relative proportions of sp² and sp³ hybridized carbon. Variation of the DC substrate bias results in dramatic modification of the film structure from the polymeric (unbiased substrates) to the diamond-like (optimized bias). It has been shown that the deposition rate and hardness of the DLC film are much higher in the H-mode deposition regime. For a 20 mTorr H-mode CH[sub 4]+Ar gas mixture discharge, the DLC film exhibits mechanical hardness of 18 GPa, Young's modulus of 170 GPa, and compressive stress of 1. [ABSTRACT FROM AUTHOR]

The unique electron field emission properties of carbon nanotube films are promising for fiat panel display application as the cold cathode. In this work, the multiwall carbon nanotube (10-10² nm in diameter, and 10³-10[sup 4] nm in length) film arrays (the pixel size: 50 µm × 50 µm) were deposited on the patterned Ni-Si substrate from hydrocarbon precursor (C[sub 2]H[sub 2]/H[sub 2]) by chemical vapor deposition at low temperature (550°C). The patterned films were characterized by scanning electron microscopy and Raman spectroscopy. The carbon nanotube film arrays exhibit good electron emission properties, e.g. low threshold emission field (below 2 V/µm), high emission current density (above 1 mA/cm² at 10 V/µm), and high emission luminance spot density on the phosphor coated-ITO(indium tin oxide)glass anode. These properties are good enough for high-resolution flat panel display application using carbon nanotube film arrays as the cathode. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrated a roughness dependent chemical vapor deposition (CVD) process to selectively grow aligned carbon nanotube bundles on silicon substrates with microscratches. Our results show that the aligned nanotubes of uniform length (around 2 μm) and diameter (20~30 nm) are assembled to nanotube bundles and in-plane vertically aligned with the microscratches. The microscratch-selective nanotube growth offers a promising approach for the fabrication of 3-D nanotube architectures in a single CVD process. [ABSTRACT FROM AUTHOR]

Ta-C and iron containing amorphous carbon (a-C:Fe) films were deposited by filtered cathodic vacuum arc technique. The influences of Fe contents on the wettability of the films were investigated in terms of surface energy. The surface energy of a-C:Fe films was determined by the contact angle measurement. Atomic force microscopy (AFM), Raman spectroscopy and X-ray induced photoelectron spectroscopy (XPS) were employed to analyze the origin of the variation of surface energy with various Fe content. It is found that the contact angle for water increases significantly after incorporating Fe into the films and the films become hydrophobic. The roughness of these films has a little effect on the contact angle. The surface energy is reduced after incorporating Fe into the a-C film which is due to the reduction of both dispersive and polar component. The reduction in dispersive component is ascribed to the decrease of atomic density of the a-C:Fe films due to the increase in sp² bonded carbon. The absorption of oxygen on the surface play an important role in the reduction of polar component for the a-C:Fe films. It is proposed that such network as (C[sub n]-O-Fe)-O-(Fe-O-C[sub n]) may be formed and responsible for the reduction of polar component. [ABSTRACT FROM AUTHOR]

Amorphous silicon-carbon alloy films have been successfully deposited by filtered cathodic vacuum arc technique. The structural and mechanical properties of the films were investigated by using x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, surface profiler and nano-indenter. The silicon content in the films determined by XPS measurement varies from 2.4 to 48 at.%. Both XPS and Raman spectroscopy show the existence of silicon carbide dusters in the films containing intermediate concentration of silicon. The silicon atoms predominately substitute the carbon atom into the carbon clusters at low silicon concentration, and form amorphous silicon carbide clusters or amorphous silicon clusters at high silicon concentration. The hardness of the films varies from 60 to 22 GPa while the stress reduces from 8.0 to 2.1 GPa. [ABSTRACT FROM AUTHOR]

A multi-party quantum summation with a single d -level quantum system is proposed, in which a semi-honest third party (TP) is employed. Only sequential communication of a single quantum d -level system (for any prime d) is required in the presented protocol, resulting in advantages in scalability. In addition, it can be realized with state-of-the-art technology. Due to the semi-honest TP, the protocol is not only secure against outside attacks, but also secure against participant attacks. [ABSTRACT FROM AUTHOR]

A simple and hydrazine-free solution-based approach for depositing (CZTS) and (CZTSSe) absorber layers is reported. The process involves incorporating metal salts and thiourea into a single pyridine-based solution, spin-coating a precursor film, and sulfurizing with sulfur powders or selenizing using pellets in an inert atmosphere, to form the desired CZTS or CZTSSe films. X-ray diffraction and Raman spectra studies show that kesterite CZTS and CZTSSe are formed after sulfurization and selenization, respectively. The selenized CZTSSe displays higher crystallinity than the sulfurized CZTS. Photovoltaic devices (glass//CZTSSe//i-/n-/A) employing the solution precursor selenized at 500°C have yielded power conversion efficiency of 1.44% under AM 1.5 illumination. [ABSTRACT FROM AUTHOR]

Collisions involving 112Sn and 124Sn nuclei have been calculated with the ImQMD transport model in order to place constraints on the density dependences of the nuclear symmetry energy. Consistent constraints on the symmetry energy at sub-saturation density have been obtained by comparing these transport calculations to measurements of isospin diffusion and to the ratios of neutron and proton spectra. New isospin diffusion results from E/A = 35 MeV are also presented. [ABSTRACT FROM AUTHOR]

Fragment yields for Z ≥ 5 from projectile fragmentation using primary beams of 36,40Ar at 50 MeV/nucleon on 64Ni target have been measured in RIBLL fragment separator. We compare the fragment cross sections with the predictions of the empirical EPAX parametrization of fragmentation cross-sections and Statistical Abration-Ablation model (SAA) by considering the RIBLL separator transmission rate. Isotope yield ratios between these two reactions were calculated and isoscaling parameters α and β are extracted, their dependences on fragment atomic number Z and neutron number N were presented. [ABSTRACT FROM AUTHOR]

HIRFL is an accelerator complex consisting of 3 accelerators, 2 radioactive beams lines, 1 storage rings and a number of experimental setups. The research activities at HIRFL cover the fields of radio-biology, material science, atomic physics, and nuclear physics. This report mainly concentrates on the experiments of nuclear physics with the existing and planned experimental setups such as SHANS, RIBLL1, ETF, CSRe, PISA and HPLUS at HIRFL. [ABSTRACT FROM AUTHOR]

Quasi-solid-state dye-sensitized solar cells were fabricated using a high molecular polymer redox electrolyte. Poly(ethylene oxide) (PEO) and Poly(vinylidenefluoride-co-hexafluoropropylene) (P(VDF-HFP)) were used to form a stable quasi-solid structure and a three-dimensional gel polymer network structure. The polymer electrolytes were composed of LiI, I2, and DMPII in the mixture of propylene carbonate (PC) and γ-butyrolactone (GBL) with different volume ratios. A metal-free organic dye (indoline dye D102) was used as a sensitizer. The ionic conductivity of the gel polymer electrolytes was measured with Electrochemical Impedance Spectroscopy (EIS). The dependence of the ionic conductivity on the volume ratio of PC to GBL was investigated. The volume ratio of the mix solvent, weight ratio of PEO/P(VDF-HFP), and the weight ratio of TiO2 fillers were optimized. The optimized quasi-solid-state cell exhibited an efficiency of 5.49% at full sunlight (air mass 1.5, 60 mW/cm2) irradiation. [ABSTRACT FROM AUTHOR]

Thermosetting polymer gel electrolytes (TPGEs) based on poly(acrylic acid)-poly(ethylene glycol) (PAA-PEG) hybrid were prepared and applied to fabricate dye-sensitized solar cells (DSCs). N-methylpyrrolidone (NMP) and γ-butyrolactone (GBL) were used as solvents for liquid electrolytes and LiI and KI as iodide source, separately. The microstructure of PAA-PEG shows a well swelling ability in liquid electrolyte and excellent stability of the swollen hybrid. The TPGE was optimized in terms of the liquid electrolyte absorbency and ionic conductivity photovoltaic performance. Quasi-solid-state DSCs containing TPGE with optimized KI electrolyte show higher efficiency, voltage, fill factor, and lower photocurrent than those with LiI electrolyte. The related mechanism was discussed. A quasi-solid-state DSC fabricated with optimized polymer gel electrolyte obtained an overall energy conversion efficiency of 4.90% under irradiation of 100 mW/cm2 (AM1.5). [ABSTRACT FROM AUTHOR]

The titanium dioxide nanotubes (TiNTs) were directly prepared from commercial P25 TiO2 powder via alkali hydrothermal transformation. The fabricated nanotubes had an average outer diameter of 8-10 nm and the inner diameter of 4-6 nm with several hundred nanometers in length. The prepared nanotubes were added into TiO2 nanoporous electrodes for the fabrication of dye-sensitized solar cells (DSCs). The photoelectrochemical characteristics and dye-adsorption properties were investigated by varying the proportion of the nanotubes incorporated into TiO2 working electrodes. The electron transport resistance, electron life time, and dye adsorption properties were evaluated in terms of electrochemical impedance spectra and photovoltaic characteristics of the solar cells. Compared to DSCs based on TiO2 nanoparticles, the fill factor, open-voltage, and photocurrent based on TiNT/P25 hybrid increased significantly. High conversion efficiency of light-to-electricity of 7.41% under illumination of simulated AM 1.5 sunlight (100 mW/cm2) was achieved for DSCs using optimized proportions of TiO2 nanotubes incorporated into TiO2 electrodes. The studies provided a promising method for the development of high efficiency and low cost DSCs. [ABSTRACT FROM AUTHOR]

Fragment yields of projectile fragmentation reactions using primary beams of 36,40Ar at 50 MeV/nucleon on 64Ni target have been measured. Fragment yields of different isotopes were obtained for Z ≥ 5 in RIBLL fragment seperator. We compare the extracted yields to the predictions of the empirical parametrization of fragmentation cross-sections(EPAX) and Statistical Abration-Ablation model(SAA) considering the RIBLL separator transmission rate. Isotope yield ratios between these 2 reactions were calculated, isoscaling parameters α and β, their dependence on fragment atomic number Z and neutron number N were calculated. [ABSTRACT FROM AUTHOR]

Single-phase CuInSe2 films were grown by high vapor selenization of CuIn alloy precursors within a partially closed graphite box. The CuIn precursors were prepared using CuxIny alloy targets with different composition rates under low vacuum level by a homemade sputtering system. The Cu and In composition rates of the used targets are 11:9, 10:10, and 9:11, respectively. The metallic precursor films were selenized using a two-step temperature profile, i.e. at 250°C and 400–500°C, respectively. The influence of the temperature at the second selenization step on the quality of the CIS absorbing layers was investigated. The CIS films were characterized by X-ray diffractometry, scanning electron microscopy, energy dispersive X-ray analysis, and Raman spectroscopy. The deposited CIS absorbers selenized at a high temperature of 500°C for 30 min exhibited a single-phase chalcopyrite structure with a preferential orientation in the (112) direction. These layers display uniform, large, and densely packed crystals with a grain size of about 3–5 μm. Cadmium sulfide buffer layer was manufactured by chemical bath deposition method. Bilayers ZnO/ZnO:Al were prepared by RF magnetron sputtering deposition. CIS solar cells with an efficiency of about 6.5% were produced without antireflective films. The method to fabricate CIS solar cells by a combination of the low vacuum sputtering deposition and the graphite box selenization process has provided a simple control process and shown a promising potential for developing high efficient and low-cost CuInSe2 solar cells. [ABSTRACT FROM AUTHOR]

The effect of annealing temperature on the magnetic and giant magnetostriction (GMS) of [Fe/Tb/Fe/Dy]n multilayer films were investigated. X-ray diffraction showed that the multilayer films' microstructures were still in amorphous at annealing temperature 300°C. The multilayer films began to crystalline at annealing temperature 400°C. The saturation magnetization of multilayer films increased by the increasing annealed temperature. The coercivity first decreased at annealing temperature 300°C and then increased when the annealing temperature was higher than 400°C. The multilayer films had good low-field GMS, and the magnetostriction of the multilayer films increased by the increasing annealing temperature. [ABSTRACT FROM AUTHOR]

An improved chemical bath deposition (CBD) technique has been provided to prepare zinc sulfide (ZnS) thin films on glass substrates deposited at 80–82°C using a mixed aqueous solution of zinc sulfate, ammonium sulfate, thiourea, hydrazine hydrate, and ammonia at the alkaline conditions. Both the traditional magnetic agitation and the substrates vibration by hand frequently were done simultaneously during the deposition. The substrates vibration reduced the formation and residence of gas bubbles on the glass substrates during growth and resulted in growth of clean ZnS thin films with high quality. Ammonia and hydrazine hydrate were used as complexing agents. It is found that hydrazine hydrate played an important role in growth of ZnS films. The structure and microstructure of ZnS films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-vis spectroscopic methods. The XRD showed a hexagonal structure. The formed ZnS films exhibited good optical properties with high transmittance in the visible region and the band gap value was estimated to be 3.5–3.70 eV. [ABSTRACT FROM AUTHOR]

The magnetic properties and giant magnetostriction effect (GMS) of the amorphous alternant [Tb/Fe/Dy]n (named S1) and [Fe/Tb/Fe/Dy]m (named S2) nano-multilayer films have been studied. The magnetic hysteresis loops show that easy magnetic direction changes from perpendicular to the film plane (S1) to parallel to the film plane (S2). S2 has better soft magnetic properties and low-field giant magnetostriction effect than that of S1, due to the exchanging interaction between the hard GMS layer and the soft layer Fe. The different magnetic behavior is explained by considering the nature of the magnetization process, i.e. domain-wall motion and spin rotation. [ABSTRACT FROM AUTHOR]

Copper indium diselenide (CuInSe2) thin films were grown on indium–tin oxide (ITO)/soda-lime glass using a one-step cathodic electrodeposition process at potentials lower than -0.6 V vs SCE, and in the presence of a large excess of In3+. The source solution contained CuCl2, InCl3, and H2SeO3 complexed by citric acid. The concentration of InCl3 in the electrochemical bath affected the structure, composition, stoichiometric ratio, and morphological properties of electrodeposited films. CuInSe2 films with a chalcopyrite structure and quite good stoichiometry were directly electrodeposited from a solution of 20 mM InCl3, 5 mM CuCl2, and 8 mM H2SeO3. Annealing of these CuInSe2 films in the temperature range from 300°C to 500°C improves their crystallinity and increases their grain size. Good chalcopyrite CuInSe2 films with a (112) preferential orientation suitable for the production of efficient solar cells are obtained after annealing at 500°C. The formation mechanism of the ternary CuInSe2 compound during the electrodeposition process was discussed. [ABSTRACT FROM AUTHOR]

A simply modified bath deposition technique has been successfully used to deposit uniform CdS thin films using cadmium chloride or cadmium acetate as the cadmium ion source, and thiourea as the sulfur source on glass substrates. Both the traditional magnetic agitation and the frequent substrate vibration by hand were done simultaneously during the deposition. Various properties of the deposited films such as surface morphology, crystallinity, and optical properties were investigated. The CdS films deposited from cadmium acetate show a good crystallinity and exhibit a preferential orientation along the hexagonal (002) direction. Their surface morphologies are more homogeneous with smaller grains than those from cadmium chloride. The CdS films prepared from both cadmium ion sources present a high optical transmission (more than 80%) in the visible range with the band gap value of about 2.4 eV. The substrate vibration reduces the formation and residence of gas bubbles on the glass substrate during growth and resulted in deposition of CdS thin films with high quality. XRD, SEM, and UV–Vis measurements have provided the supported data. The fundamental CBD growth mechanisms involving different cadmium salts are discussed. [ABSTRACT FROM AUTHOR]

Intrinsic zinc oxide (i-ZnO) film was prepared for CuInSe2 (CIS) solar cell application [L. Stolt and J. Hedstrom, Appl. Phys. Lett.62 (1993) 8; D. Rudmann, Ph.D. Thesis, University of Basel, Basel, (2004)] on glass substrate by inductively coupled plasma (ICP)-assisted DC magnetron sputtering and under a quite low temperature of 50°C. The sputtering was done in an Ar and O2 gas mixture and a ceramic ZnO target was used. The microstructures of the film were investigated by X-ray diffractometer and scanning electron microscope. It was shown that all of the films had a c-axis preferred orientation perpendicular to the substrate. In our work, film with resistivity of 7 × 108Ω·cm and transmittance of about 80% in the visible range was prepared under the conditions of 4 mTorr working pressure and 50°C temperature. [ABSTRACT FROM AUTHOR]

The dynamics and the conditions of amorphous transitions induced in a Ge1Sb2Te4 system upon a single femtosecond (fs) pulse melting were studied by real-time reflectivity measurements. The system has a multilayer structure of 100 nm ZnS–SiO2/(15–100 nm) Ge1Sb2Te4/120 nm ZnS–SiO2/0.6 mm polycarbonate substrate. It is shown that under optimum conditions amorphization is completed within 900 ps. The thickness of the phase change layer plays an important role in controlling the heat flow conditions in the system upon a fs pulse irradiation. The use of the fs laser pulse leads to a situation in which the pulse energy is deposited within a very short time in a thin surface layer, leading to heating or melting. The so-generated steep temperature gradient is subsequently smoothed by heat diffusion toward the substrate. The relative thermal process and effects are estimated. The calculated results are consisted with those from real-time reflectivity measurements. The mechanism of crystalline to amorphous transition triggered by single fs laser pulses is discussed. [ABSTRACT FROM AUTHOR]

Electrosorption of carbon nanotube and nanofiber (CNT–CNF) composite film electrodes was studied as a new desalination technology. The CNT–CNF composite film electrodes were grown on nickel sheets by low pressure thermal chemical vapor deposition. Different growth conditions at different acetylene flow rates of CNT–CNF composite film electrodes have been performed to obtain different crystallinities. The electrosorption experiments and Raman spectra analysis show the successful removal of ions with CNT–CNF composite film electrodes, depending on the optimal degree of crystalline perfection. In our work, optimal electrosorption was realized for the CNT–CNF composite film electrodes growing at 550°C with the acetylene and hydrogen flow rates of 30 and 200 sccm. [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO) thin films were prepared by radio frequency (RF) magnetron sputtering and under a quite low vacuum level of 2.3 × 10-3Pa. The sputtering was done in an Ar and O2 gas mixture at a temperature of 200°C. A ceramic In2O3:SnO2 target (10 wt% SnO2) was used. The microstructures of the films were investigated by a field emission scanning electron microscope (FESEM) and an X-ray diffractometer (XRD). X-ray photoelectron spectroscopy (XPS) was performed to characterize the composition of the films. ITO films with a high transparency in the visible wavelength range (80–95%) were obtained. The dependency of the electrical, optical and structural properties of ITO films on both the O2 flow ratio (O2/(O2 + Ar)) and the working pressure was investigated. In the case of low working pressure (1 Pa), the more highly transparent and conducting films were produced at the lower O2 flow ratio. High working pressure (2 Pa) gave rise to low quality, low transparency and amorphous films. Under RF sputtering at low vacuum level, the main contribution to the chamber atmosphere is due to water vapor. Oxygen originating from water vapor dissociation induced by plasma plays the same role as an oxygen or water vapor flux usually intentionally introduced in the system in order to have good quality films. [ABSTRACT FROM AUTHOR]

The longitudinal momentum (p//) distributions of fragments after one-proton removal and reaction cross sections (σR) for several N = 10 isotones at intermediate energy (~ 70A MeV) have been measured simultaneously at the RIken Projectile fragment Separator (RIPS). p// was measured using a direct time-of-flight (TOF) technique, while σR was determined using a transmission method. An enhanced σR is observed for 23Al comparing with its neighbors. The p// distribution for 22Mg fragments from 23Al one-proton removal reaction has been obtained for the first time. The experimental data are discussed within a Few Body Glauber (FBG) framework. Analysis of p// indicates a dominant d-wave component in the ground state of 23Al. This agrees with recent experimental results. We also suggest the possibility of an enlarged 22Mg core for proton-rich nucleus 23Al. [ABSTRACT FROM AUTHOR]

Polycrystalline silicon carbide (P-SiC) films containing SiC nanoparticles and Er were prepared by r.f. reactive magnetron co-sputtering technique with SiC and Er targets on low-temperature silicon (111) and silicon dioxide substrates with the mixed gas of pure argon, methane, and hydrogen. Surface morphology and photoluminescence (PL) properties of them were measured by field-emission scanning electron microscope and Raman spectroscopy. The peak position, intensity, and the full width at half maximum (FWHM) of PL spectra were relevant with Er doping levels and deposition conditions. [ABSTRACT FROM AUTHOR]

Systematic experimental researches on reverse transition in the boundary layer on a heated plate are carried out, and the time-series of instantaneous velocity components and temperature fluctuation are measured, then the Reynolds stress, the production term and absorption term of turbulent energy are presented. From the experimental results, the characteristics and physics mechanism of reverse transition as well as statistical properties of turbulence during reversion are revealed. [ABSTRACT FROM AUTHOR]

A solution process was used to grow SrTiO3 (STO) buffer layers on LaAlO3 (LAO) and biaxially textured Ni substrates by spin coating technique. The epitaxial STO film obtained has strong cube texture and uniform microstructure. A metal organic decomposition process using trifluoroacetate precursors was applied to deposit YBa2Cu3O7-δ (YBCO) thin films on these buffer layers. The YBCO/STO/LAO was biaxially textured and the TConset and ΔTC is 90.1K and 2.7K, respectively. [ABSTRACT FROM AUTHOR]