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Different from the extensive experimental investigations into the thermoelectric (TE) properties of the bulk IV–VI compounds, less attention has been paid to the TE properties of the monolayer IV–VI compounds. Here, we consider the TE transport properties including the Seebeck coefficient, electronic conductance, thermal conductance, power factor, and figure of merit Z T of the undoped and Bi-doped GeS monolayers. Our results show that for both the undoped and Bi-doped monolayers the anisotropy is widely observed in all their TE properties, and the maximum Z T at a certain temperature along the armchair direction is much greater than that along the zigzag direction. Moreover, Bi doping can lead to an increase of the maximum Z T , and there are more Z T peaks appearing near the zero chemical potential. This indicates that the Bi-doped GeS monolayer can work as a TE material at a lower bias voltage, and especially along the armchair direction it can work at zero bias voltage, which obviously strengthens the reliability of the TE devices. As the temperature increases, the maximum Z T will be uniformally increased along the armchair and zigzag directions for both the undoped and Bi-doped GeS monolayers. In the temperature scope from 300 to 800 K, the maximum Z T along the armchair direction of the Bi-doped GeS monolayer will increase from 3.39 to 4.85, which indicates that this Bi-doped GeS monolayer is a promising TE material in a wide-temperature zone. As an application, we have designed the GeS-based TE couples and found that their efficiencies can be greater than 27 % at large temperature differences. This research should be an important guidance for designing a low-voltage, wide-temperature-scope, and high-stability TE device. [ABSTRACT FROM AUTHOR]

The surface optical (SO) phonon replica in photoluminescence (PL) spectroscopy of nitride nanowires (NWs) was theoretically investigated in this study. The dispersive relationships of SO phonon mode in anisotropic wurtzite (WZ) and isotropic zinc-blende (ZB) crystal structure NWs with circular and square cross sections (CSs) were derived within the framework of the dielectric continuum model. Based on the energy and momentum conservation laws, a constraint relationship between the frequency and wave-number was constructed for SO phonon-assisted excitonic PL spectra in the NW structure. By combining the dispersive and constraint relationships, the frequency and wave-number of the SO phonon replica in the PL spectra could be determined. The WZ and ZB crystal structures of nitride semiconductor were considered. The influences of surface factors including the CS shape, dielectric medium, and environment temperature on the frequency and photon wavelength of the band-edge emission of the SO phonon replica were studied in detail. Numerical results reveal that the crystal structure, surface factors, and environment temperature greatly affect the frequency and photon wavelength of the band-edge emission of the SO phonon replica. The calculated results for the photon wavelength agree well with the experimental values of the SO phonon replica in AlN NWs. The results of the dielectric effect obtained here are also supported by previous experimental and theoretical results for nitrides and other semiconductor NWs. The present theoretical scheme and numerical results can be used to analyze and design the SO phonon replica in PL spectra of nanostructures. [ABSTRACT FROM AUTHOR]

Shubnikov–de Haas (SdH) oscillations and the quantum Hall effect (QHE) can give insights into quantum oscillations of charge carriers. We report the SdH oscillations and QHE of magnetically doped topological insulator FexBi2−xSe3 crystals, in which the lattice constant c decreases with the increasing dopant concentration but increases when x is greater than 0.08. From the fitting of low-temperature magnetoresistance data to the Lifshitz–Kosevich formula, the effective mass of the carriers and the Dingle temperature of the samples were extracted and show a similar trend of change as the lattice constant. A constant step size of 1/Rxy observed during Hall measurements at low temperatures implies two-dimensional-like transport behavior associated with the layered structure of the doped Bi2Se3 samples. Two-dimensional and three-dimensional charge carrier densities were calculated, and the latter had a similar trend of change as the lattice constant. A systematic study of the changes in all these properties with increasing dopant concentration suggests that they are highly correlated. [ABSTRACT FROM AUTHOR]

Magnetic skyrmions are attracting considerable interest in scientific research and practical applications. Recently, a novel phenomenon was observed in which a skyrmion bubble lattice could be induced by a slightly tilted in-plane magnetic field in a multilayer film. In this article, the formation process of a skyrmion bubble lattice was investigated by micromagnetic simulation considering the Dzyaloshinskii–Moriya (DM) interaction and distribution of magnetic anisotropy. The exchange field that prevents the reversal of moments was minimized when the magnetic moments were aligned by a slightly tilted in-plane magnetic field. Many small reversed domains were formed in the regions where the demagnetization field conquers the anisotropy field after the removal of the external field and developed into a stable skyrmion bubble array. The DM interaction has an obvious influence on the size and precise moment structure of the stable skyrmion bubbles but has little effect on the nucleation of reversed domains. [ABSTRACT FROM AUTHOR]

Shock-induced opacity in Gd3Ga5O12 (GGG) single crystals is investigated by transmission/ emission measurements at 16 wavelengths (400-800 nm), as well as complementary particle velocity measurements at 1550 nm, in the pressure range of 47-211 GPa. Optical transmission spectra through the shocked samples are measured with a in-situ, shock-generated light source, and the resultant extinction coefficients of different wavelengths and shock pressures obtained. As shock strength increases, the optical opacity of the shocked GGG increases and peaks at 75 GPa (the transparent-opaque transition), drops at 75-100 GPa (the opaque-transparent transition), and then increases again. The transparency recovery coincides with a solid-solid phase transition. The microstructure changes associated with the solid-solid phase transition and plastic deformation most likely cause the loss and recovery of transparency. GGG can be useful as a high pressure window for laser velocimetry (1550 nm) or optical pyrometry (400-800 nm) in the ranges of 100-140 GPa and 80-120 GPa, respectively. [ABSTRACT FROM AUTHOR]

Refractive indices of [111] Gd3Ga5O12 single crystals under shock compression are investigated with planar impact and high-speed laser velocimetry, in the pressure range of 100-290 GPa. The refractive index, n, at 1550 nm is obtained as a function of shock pressure or density (q). n increases as pressure increases from 106 GPa to 201 GPa, and then drops sharply as a result of shock-induced melting; the n - q relation is linear for the high pressure solid phase. We also establish the true particle velocity-apparent velocity relation for velocity correction. [ABSTRACT FROM AUTHOR]

SnO2 quantum dots (QDs) are potential materials for deep ultraviolet (DUV) light emitting devices. In this study, we report the temperature and excitation power-dependent exciton luminescence from SnO2 QDs. The exciton emission exhibits anomalous blue shift, accompanied with band width reduction with increasing temperature and excitation power above 300K. The anomalous temperature dependences of the peak energy and band width are well interpreted by the strongly localized carrier thermal hopping process and Gaussian shape of band tails states, respectively. The localized wells and band tails at conduction minimum are considered to be induced by the surface oxygen defects and local potential fluctuation in SnO2 QDs. [ABSTRACT FROM AUTHOR]

Here, we report the successful synthesis of a spin- and charge-decoupled diluted magnetic semiconductor (DMS) (Ca,Na)(Zn,Mn)2As2, crystallizing into the hexagonal CaAl2Si2 structure. The compound shows a ferromagnetic transition with a Curie temperature up to 33K with 10% Na doping, which gives rise to carrier density of np∼1020cm-3. The new DMS is a soft magnetic material with HC<400 Oe. The anomalous Hall effect is observed below the ferromagnetic ordering temperature. With increasing Mn doping, ferromagnetic order is accompanied by an interaction between the local spin and mobile charge, giving rise to a minimum in resistivity at low temperatures and localizing the conduction electrons. The system provides an ideal platform for studying the interaction of the local spins and conduction electrons. [ABSTRACT FROM AUTHOR]

When rigid and stretchable components are integrated onto a single elastic carrier substrate, large strain heterogeneities appear in the vicinity of the deformable-non-deformable interfaces. In this paper, we report on a generic approach to manufacture hybrid stretchable circuits where commercial electronic components can be mounted on a stretchable circuit board. Similar to printed circuit board development, the components are electrically bonded on the elastic substrate and interconnected with stretchable electrical traces. The substrate—a silicone matrix carrying concentric rigid disks—ensures both the circuit elasticity and the mechanical integrity of the most fragile materials. [ABSTRACT FROM AUTHOR]

Real-time monitoring of optical anisotropy during growth by the chemical mist deposition of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films was carried out using spectroscopic ellipsometry. The microstructure of the grown films was found to be primarily determined by the DC bias applied to the mesh electrode. The ellipsometry results revealed that uniaxial anisotropy appeared for film thicknesses of about 5 nm and above, which corresponds to the average size of PEDOT crystallites. The extraordinary refractive index was found to be strongly correlated with the carrier mobility. Both the degree of optical anisotropy and the carrier mobility could be controlled during film growth by adjusting the DC bias. [ABSTRACT FROM AUTHOR]

We investigated the graphene oxide (GO) based n-type crystalline silicon (c-Si)/conductive poly(ethylene dioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) Schottky junction devices with optical characterization and carrier transport measurement techniques. The optical transmittance in the UV region decreased markedly for the films with increasing the concentration of GO whereas it increased markedly in the visible-infrared regions. Spectroscopic ellipsometry revealed that the ordinary and extraordinary index of refraction increased with increasing the concentration of GO. The hole mobility also increased from 1.14 for pristine film to 1.85 cm2/V s for the 12-15 wt. % GO modified film with no significant increases of carrier concentration. The highest conductivity was found for a 15 wt. % GO modified PEDOT:PSS film: the c-Si/PEDOT:PSS:GO device using this sample exhibited a relatively high power conversion efficiency of 11.04%. In addition, the insertion of a 2-3 nm-thick GO thin layer at the c-Si/PEDOT:PSS interface suppressed the carrier recombination efficiency of dark electron and photo-generated hole at the anode, resulting in the increased photovoltaic performance. This study indicates that the GO can be good candidates for hole transporting layer of c-Si/PEDOT:PSS Schottky junction solar cell. [ABSTRACT FROM AUTHOR]

Dielectric spectra and magnetization hysteresis loops were used to investigate the grain size effect with temperature on the electrical and magnetic response of co-precipitation derived spinel (Ni0.5Zn0.5)Fe2O4 (NZFO) ceramics. Remarkable dielectric relaxation phenomena of non-Debye type have been observed in each NZFO ceramics as confirmed by two kinds of Cole-Cole plots of the 1100 °C sintered samples, mainly due to the electron-hopping mechanism between n-type and p-type carriers and interfacial ion effect when applied an increase of temperature. The high and low response of grain and grain-boundary regions were determined by modeling the impedance experimental results on two equivalent RC circuits taking into account grain deep trap states. By employing the modified Arrhenius equation, activation energy values of different sintering temperatures were calculated and analyzed in combination with oxygen vacancy. In addition, the magnetization of various sintering temperature samples is dominated by cation distribution and surface effect in different particle ranges. [ABSTRACT FROM AUTHOR]

In nano-grain BaTiO3 ceramics, internal compressive stresses make the cubic phase more stable, while internal shear stresses stabilize rhombohedral and orthorhombic phases. The competition between internal compressive stresses and internal shear stresses gives a ferroelectric to paraelectric to ferroelectric reentrance phenomenon as a function of grain size. The pressure can be a tuning factor of reentrance behavior by controlling the interactions between external hydrostatic pressure and internal compressive stresses. These experimental phenomena can be well described by a modified Ginzburg-Landau-Devonshire thermodynamic theory. [ABSTRACT FROM AUTHOR]

The combined effect of the spin-transfer torque and circular Amperian field to the switching of the chiralities of the dual-vortex magnetization in multilayered Ni80Fe20/Cu/Co nanopillar elements (o\ = 100 nm) is investigated numerically. It is demonstrated that, by passing a current pulse through the nanopillar, the chirality of the Ni80Fe20 layer can be controllably switched while that of the fixed Co layer persists. Consequently, reliable toggle switching between bistable low- and high-MR states can be achieved by applying current pulses with appropriate amplitude, polarity, and duration. It is found that the magnetization dynamics after the onset of a current pulse includes the excitation of spin-wave eigenmodes and that the predominant process throughout is the precessional motion of the free-layer magnetization. A shift of the eigenfrequency is observed when the chirality of the free-layer vortex magnetization switches from parallel to antiparallel relative to that of the fixed layer. This frequency shift is attributed to dynamic magnetostatic coupling between the vortices. [ABSTRACT FROM AUTHOR]

The recently discovered three-dimensional topological insulator Bi2Te3 is studied as function of pressure in terms of crystal structures, resistance, and Hall coefficient. The superconductivity is found in phase I (ambient phase) Bi2Te3 with Tc ∼ 3 K, which is related to the topological features. The evolution of crystal structure with pressure is investigated by high pressure synchrotron radiation experiments that reveal structural transitions occurring at about 8 GPa, 13 GPa, and 16 GPa, respectively. Furthermore, the high pressure phases of Bi2Te3 are also superconducting but with much higher Tc ∼ 8 K. The superconducting transitions are compared with those for Bi, Te elements. A global phase diagram of Bi2Te3 as function of pressure up to 30 GPa is obtained. [ABSTRACT FROM AUTHOR]

We investigate plasmon-enhanced upconversion (UC) fluorescence in Yb3+-Er3+-Gd+3 codoped sodium yttrium fluoride (NaYF4:Yb/Er/Gd) nanorods using gold nanoparticles or nanoshells. A simple method was proposed for the preparation of core/shell NaYF4/Au structures, with dispersed Au nanoparticles or uniform Au coating on the surface of the UC nanorod. Pure hexagonal-phase NaYF4:Yb/Er/Gd nanorods were synthesized via a liquid-solid reaction in oleic acid and ethanol solvent. A one-step approach was introduced to modify the hydrophobic surfaces of the as-deposited NaYF4:Yb/Er/Gd nanorods. After this surface modification, Au nanoparticles or nanoshells were successfully attached on the surfaces of NaYF4:Yb/Er/Gd nanorods. The as-deposited UC nanorods showed a strong UC emission in green and red bands under 980 nm laser excitation. The attachment of Au nanoparticles onto NaYF4:Yb/Er/Gd nanorods resulted in a more than three-fold increase in UC emissions, whereas the formation of continuous and compact Au shells around the nanorods suppressed the emissions. The related interaction mechanisms of the UC emission of NaYF4:Yb/Er/Gd nanorods with plasmon modes in Au nanostructures are analyzed and discussed. [ABSTRACT FROM AUTHOR]

Room temperature ferromagnetic Zn0.95Co0.05O thin films with (002) preferential orientation have been successfully deposited by pulsed laser deposition at different oxygen partial pressures on n-type (100) silicon substrate. A maximum saturation magnetization of 0.86 μB/Co was achieved at room temperature at 5 × 10-6 Torr oxygen partial pressure. HRTEM and XPS results indicate that the observed ferromagnetism is not due to metallic Co microclusters in the thin films. Oxygen vacancies in the films were detected from photoluminance characterization, which showed a significant effect on the ferromagnetic behavior. By changing the amount of oxygen vacancies through adjusting the oxygen partial pressure during deposition and post-deposition annealing, the ferromagnetic behavior of the thin films can be tuned significantly. This implies that the oxygen vacancies, which contribute to the bound magnetic polarons model and RKKY indirect interaction, are the likely cause of this ferromagnetism. [ABSTRACT FROM AUTHOR]

A rigorous technique of monitoring the vertical column density (VCD) of NO2 by using the scattered solar radiation is reported. By analyzing the optical path, the method of collecting the useful scattered solar radiation is achieved. By using this method, the collecting equipment and procedure of solar radiation could be greatly simplified. And through the actual measurement, it is proved that the VCD of NO2 measured by using the scattered solar radiation is very close to that from the direct solar radiation. [ABSTRACT FROM AUTHOR]

Perovskite-type transparent and conductive oxide films, Sb-doped SrSnO3 (SSSO), were grown on SrTiO3(001) substrates by the pulsed laser deposition method. It is revealed that the films can be grown at relatively lower temperatures and show high single crystallinity with a cubic perovskite structure with lattice constant of 4.036 Å. These films show good optical transmittance in the visible range, with the direct allowed band gap of 4.53 eV, and behave as an n-type semiconductor with resistivity of 23 mΩ cm at room temperature. The effect of growth temperature on structural, electrical, and optical properties of the SSSO films was probed, and a diode based on n-SSSO/p-La0.67Ca0.33MnO3 structure was also demonstrated. [ABSTRACT FROM AUTHOR]

Perovskite-type transparent and conductive oxide films, Sb-doped SrSnO3 (SSSO), were grown on SrTiO3(001) substrates by the pulsed laser deposition method. It is revealed that the films can be grown at relatively lower temperatures and show high single crystallinity with a cubic perovskite structure with lattice constant of 4.036 Å. These films show good optical transmittance in the visible range, with the direct allowed band gap of 4.53 eV, and behave as an n-type semiconductor with resistivity of 23 mΩ cm at room temperature. The effect of growth temperature on structural, electrical, and optical properties of the SSSO films was probed, and a diode based on n-SSSO/p-La0.67Ca0.33MnO3 structure was also demonstrated. [ABSTRACT FROM AUTHOR]

This article reports on the study of microstructure and dislocation of InN films using high resolution x-ray diffraction grown on sapphire (0001) both by metalorganic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE). The mosaic tilt, twist, and correlation lengths of InN films are determined by using symmetrical and asymmetrical reflections as well as reciprocal space mapping. Deducing from these results, MBE-grown InN film exhibits the edge-type dislocations of 4.0×109 cm-2, which is about ten times higher than the density of screw-type dislocations. In MOCVD-grown InN sample, the edge-type dislocations density is as high as 2.1×1010 cm-2, and the screw-type dislocations density is 1.3×109 cm-2. They indicate that edge type is the predominant dislocation type in the InN films. By comparing the reported transmission electron microscopy results, the accuracy of evaluation for the dislocation density using the mosaic model is proved. [ABSTRACT FROM AUTHOR]

Room temperature ferromagnetic Zn0.95Co0.05O thin film with (002) preferential orientation has been deposited by pulsed laser deposition at different substrate temperatures on n-type (100) silicon substrate. A maximum saturation magnetization of 0.86μB/Co was achieved at room temperature. High-resolution transmission electron microscope and x-ray photoelectron spectroscopy results indicate that this ferromagnetism behavior is not due to Co microclusters in the thin film. Zinc interstitials, oxygen vacancies, and lattice defects induced by low substrate deposition temperature show a significant effect on ferromagnetic behavior. By changing the substrate deposition temperature to control the amount of zinc interstitials, oxygen vacancies, and lattice defects, ferromagnetism can be tuned significantly as well, which is a direct evidence that these defects contributed to the ferromagnetism in ZnO:Co thin films. [ABSTRACT FROM AUTHOR]

Barium zirconate titanate Ba(Zr0.2Ti0.8)O3 (BZT) thin films on La0.7Sr0.3MnO3 (LSMO)-coated Si and Pt/Ti/SiO2/Si substrates have been prepared by pulsed laser deposition and crystallized in situ at 650 °C. Four capacitor types of LSMO/BZT/LSMO/Si, Pt/BZT/LSMO/Si, Pt/BZT/Pt/Si, and Pt/BZT/LSMO/Pt/Si were prepared to investigate the structural and dielectric properties, tunability, and figure of merits. Among them, the high (100)-oriented BZT films were grown on the (100)-textured LSMO and (111)-textured Pt electrodes. The results show that the LSMO/BZT/LSMO/Si has the highest dielectric constant of 555 and Pt/BZT/LSMO/Pt/Si has the highest tunability of 73% at 1 MHz. The high dielectric constant and tunability have been attributed to the (100) texture of the LSMO bottom layer leading to the decrease of the thickness of the interface of the dead layer. [ABSTRACT FROM AUTHOR]

Visible and infrared photoluminescence was observed from AlN:Er films grown by reactive radio-frequency magnetron sputtering under different powers. X-ray diffraction indicates that the films have a c-axis oriented hexagonal wurtzite structure with an average crystallite size of about 59–83 nm and a strain of about (1.12–1.69)×10-3. Green emissions (∼540 and 558 nm) from the AlN:Er films are due to the intra-4fn transition of Er3+ from 2H11/2 and 4S3/2 to 4I15/2, and infrared (∼1535 nm) emissions correspond to 4I13/2 to 4I15/2 transitions. Increasing the sputtering power results in larger grain size, lower strain, and enhancement of the luminescence intensity. [ABSTRACT FROM AUTHOR]

Presents a detailed characterization of the ordered structure in silicon-doped Ga[sub0.51]In[sub0.49]P. Influence of silicon doping on the ordering in GaInP layers; Analysis of undoped layers grown at various substrate temperatures; Relationships between photoluminescence peak energy and electron concentration of silicon-doped samples at room temperature.

Presents information on a study which examined a carrier current balance model for surface photovoltage. Details of the theoretical model employed in the study; Discussion; Conclusion.

Deals with a study which investigated the effect of strain-induced band-gap modulation in a GaAs/AlGaAs multiple-quantum-well structure with the wells located at various depths in the structure. Background to the study; Experimental procedures; Results and discussion.

Presents a study which examined highly carbon-doped gallium arsenide epilayers grown by low-pressure metalorganic vapor phase epitaxy using high-resolution x-ray diffraction. Information on carbon-doping; Methodology; Results.

Focuses on a study which presented a photoluminescence (PL) analysis of gallium indium phosphide/gallium arsenide single-quantum well structures grown by metal-organic vapor-phase epitaxy. Description of the sample and procedure; Estimation of the growth temperature dependent conduction and valence band discontinuity of the heterojunction; Results of x-ray diffraction measurements and simulations.

Deals with a study that investigated the use of thin film technology to introduce controllable and thermally stable stress into semiconductor heterostructures. Reason for the reproducibility and controllability of the induced stress in the structure; Dependence of the stability of the stress; Interrelationship between the photoelastic waveguide characteristics and the stress.

Presents a study that investigated gallium compound interfaces grown by low-pressure metalorganic vapor phase epitaxy at various temperatures and in different structures. Use of photoluminescence method; Results of the examination on gallium compound using x-ray diffraction measurements and simulations with dynamical theory.

Studies the use of high resolution x-ray diffraction thin indium arsenide and gallium arsenide layers grown on InP substrates by low-pressure metalorganic vapor-phase epitaxy. Growth parameter and structural parameter of the investigated samples; Superlattice periods determined from the observed satellites separations; Enlargement of an experimental rocking curve of sample IX in the vicinity of the zeroth-order peak.

Investigates single-element contracts, palladium or nickel, on various p-InP susbstrates grown by liquid-encapsulation Czochralski and by metal-organic chemical vapor deposition. Procedures used to evaluate the substrates; Factor responsible for the observed difference in ohmic behavior; Description of the proposed defect-assisted tunneling mechanism.

Focuses on a study which described the use of elevated temperature implantation to simultaneously achieve compositional disordering and electrical isolation and form guided-wave modulators using oxygen ion beam mixing. Insight on indium phosphide (InP)-based ion-beam mixing devices; Description of results on elevated temperature oxygen ion beam mixing in InP-based superlattices; Discussion on the photoelastic effect in InP-based structures.

By micromagnetic simulation, we investigated a double 360° domain walls system in two parallel nanowires. Two domain walls are coupled to each other via magnetostatic interaction. When a spin-polarized current is applied to only one nanowire or both nanowires with the same direction, the two domain walls propagate along nanowires together. The critical velocity of such system is obviously higher than that of a single 360° domain wall. The interaction between the two domain walls can be modeled as two bodies that connected by a spring, and we analyzed the coupling characteritics of the double 360° domain walls at last. [ABSTRACT FROM AUTHOR]

Dy doped α-SiAlON ceramics prepared by the hot-pressing method show a high optical transmittance value, >70%, in the infrared region of 1.5–4.5 μm. First principles calculations have been carried out to reveal the underlying transparency mechanism. It is found that the valence shell of doped Dy atoms interacts strongly with the doping states of α-SiAlON, resulting in the increase in the optical gap from 0.4 to 1.1 eV, which suppresses the photoabsorption in the wavelength region longer than 1.0 μm and leads to the good transparency property. The calculated optical transmission spectra are in good agreement with the corresponding experiments. [ABSTRACT FROM AUTHOR]

We report that (La0.07Ba0.93)SnO3 films grown epitaxially on SrTiO3(001) substrates by laser ablation at 760 °C show a cubic perovskite structure of lattice constant 4.121 Å, excellent optical transmittance in the visible range, and a weak metallic behavior with low resistivity of about 4 mΩ cm within 10–300 K. The transparent perovskite oxide films are n-type conductors, with carrier concentration and mobility at room temperature of about 2×1021 cm-3 and 0.69 cm2/V s, respectively, and a direct allowed band gap of 4.02 eV. The effect of deposition temperature on structural, optical, and electric properties of the Sb-doped Ba(Sn0.93Sb0.07)O3 films was also demonstrated. [ABSTRACT FROM AUTHOR]

We report that (La0.07Ba0.93)SnO3 films grown epitaxially on SrTiO3(001) substrates by laser ablation at 760 °C show a cubic perovskite structure of lattice constant 4.121 Å, excellent optical transmittance in the visible range, and a weak metallic behavior with low resistivity of about 4 mΩ cm within 10–300 K. The transparent perovskite oxide films are n-type conductors, with carrier concentration and mobility at room temperature of about 2×1021 cm-3 and 0.69 cm2/V s, respectively, and a direct allowed band gap of 4.02 eV. The effect of deposition temperature on structural, optical, and electric properties of the Sb-doped Ba(Sn0.93Sb0.07)O3 films was also demonstrated. [ABSTRACT FROM AUTHOR]

Design of head interconnect is one of the important issues for hard disk drives with higher data rate and storage capacity. The impedance of interconnect and electromagnetic coupling influence the quality level of data communication. Thus an insightful study on how the trace configuration affects the impedance and crosstalk is necessary. An effective design approach based on Taguchi's robust design method is employed therefore in an attempt to realize impedance matching and crosstalk minimization with the effects of uncontrollable sources taken into consideration. [ABSTRACT FROM AUTHOR]

We report the crystal structure and magnetic properties of the Zn1-xMnxO compounds synthesized by a combustion method. The Zn1-xMnxO compounds with x=0–0.1 crystallize in the wurtzite ZnO structure. The lattice parameters a and c of Zn1-xMnxO increase linearly with the Mn content, indicating that Mn2+ ions substitute for Zn2+ ions. Scanning electron microscopy shows that the average particle radius of Zn0.95Mn0.05O is about 40 nm. From the Curie–Weiss behavior of susceptibility at high temperature, it was found that the Mn–Mn interaction is dominated by antiferromagnetic coupling with effective nearest-neighbor exchange constant J about -32 K and the large negative value of the Curie–Weiss temperature. [ABSTRACT FROM AUTHOR]

The crystal structure and superconducting properties of RuSr[sub 2-x]Ba[sub x]GdCu[sub 2]O[sub 8] (0<=x<=0.1) have been investigated. X-ray powder diffraction (XRD) patterns show that the solid solution range is 0<=x<=0.1. The superconducting transition temperature was raised up to 35 K (zero) and 62 K (onset) for x=0.07, from 16 K (zero) and 45 K (onset) for x=0.0, and then T[sub C] decreases with x when x>0.07. Rietveld refinement for XRD data of RuSr[sub 2-x]Ba[sub x]GdCu[sub 2]O[sub 8] show that the apical Cu–O(1) bond length increases with an increase of x, while the Ru–O(1) bond length decreases, This may account for the enhancement of the superconducting transition temperature. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

To investigate light emission and dynamic deformation behaviors, sapphire (single crystal Al2O3) samples with three crystallographic orientations (a, c, and r-cut) were shock-compressed by the planar impact method, with final stress ranges from 47 to 65 GPa. Emission radiance and velocity versus time profiles were simultaneously measured with a fast pyrometer and a Doppler pin system in each experiment. Wave profile results show anisotropic elastic-plastic transitions, which confirm the literature observations. Under final shock stress of about 52 GPa, lower emission intensity is observed in the r-cut sample, in agreement with the previous report in the literature. When final shock stress increases to 57 GPa and 65 GPa, spectral radiance histories of the r-cut show two stages of distinct features. In the first stage, the emission intensity of r-cut is lower than those of the other two, which agrees with the previous report in the literature. In the second stage, spectral radiance of r-cut increases with time at much higher rate and it finally peaks over those of the a and c-cut. These observations (conversion of intensified emission in the r-cut) may indicate activation of a second slip system and formation of shear bands which are discussed with the resolved shear stress calculations for the slip systems in each of the three cuts under shock compression. [ABSTRACT FROM AUTHOR]

A correction to the article "Optical and Carrier Transport Properties of Graphene Oxide based crystalline-Si/organic Schottky Junction Solar Cells" that was published in the 2013 issue is presented.

Recently, the magnetocaloric effect (MCE) of Ni-Mn-based Heusler alloys has attracted more attention due to its metamagnetic shape-memory effect. However, most MCE investigations focused on the bulk alloys developed at high magnetic field (>2 T). In this paper, by employing the melt-spinning technique, a large MCE at low magnetic field was found in a ribbon of Ni50-xCoxMn35In15. The magnetic entropy change ΔS reaches the maximum value of 5.35 J/kg K at 1 T field in the Ni49CoMn35In15 ribbon near room temperature, and its corresponding temperature span arrives 24 K. The refrigerant capacity is enhanced with the increase of the Co substitution. Such a large MCE at low magnetic field in the Ni50-x CoxMn35In15 ribbon with a wide temperature range provides a potential candidate for room temperature magnetic refrigeration. [ABSTRACT FROM AUTHOR]

W-type barium hexaferrite platelets Ba(ZnxCo1-x)2Fe16O27 (0.1 ≤ x ≤ 0.9) were prepared by a chemical coprecipitation route. The results of field-emission scanning electronic microscopy showed that the grains were regular hexagonal platelets with sizes from 0.5 to 1.5 μm. With increasing x, the coercivity decreased, whereas the saturation magnetization increased. Microwave absorption properties were investigated in the frequency range of 8-12 GHz. An optimal reflection loss (-24.8 dB) reached at 10 GHz for x = 0.5 with a thickness of 2 mm. These results indicated that our samples might be a potential candidate for permanent magnets and microwave absorption materials. [ABSTRACT FROM AUTHOR]

A correction to the article "Microstructure and dislocation of epitaxial INN films revealed by high resolution x-ray diffraction," published online on August 7, 2008, is presented.

We measured the mechanical properties of dense and porous polymeric films, the modified polyarylethers, which have a low dielectric constant varying from 2.7 to 1.8, by combining three different methods; membrane bulge test, nanoindentation, and single-substrate bending beam method. The elastic modulus and initial stress measured from these three methods are in good agreement. The substrate effect was observed in the measurements by nanoindentation. Data obtained by nanoindentation show a significant dependence on the film thickness and the displacement depth of the indenter. However, the hardness of the low dielectric constant thin film does not depend on thickness and only slightly depends on the indentation depth. A tentative analysis is proposed to explain the results. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

FeCoCd thin films with 500 nm thickness are directly prepared through electrodeposition in the sulphate bath in which glycine and citric acid were added as complex agents. The composition, structure, and magnetic of FeCoCd films were investigated as a function of Cd 2+ concentration, cathode current density, and deposition temperature. A wonderful soft magnetic FeCoCd film was prepared and its coercivity of easy axis and hard axis are 5 Oe and 4 Oe, respectively. The natural resonance frequency is about 3.0 GHz, which imply that the FeCoCd film is potential candidate for high frequency applications.