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The morphology and crystal structure of Pt films grown by pulsed laser deposition (PLD) on yttria-stabilized zirconia (YSZ)at high temperatures Tg = 900 °C was studied for four different film thicknesses varying between 10 and 70 nm. During the subsequent growth of the capping layer, the thermal stability of the Pt was strongly influenced by the Pt film's thickness. Furthermore, these later affected the film morphology, the crystal structure and hillocks size, and distribution during subsequent growth at Tg = 900 °C for a long duration. The modifications in the morphology as well as in the structure of the Pt film without a capping layer, named also as the as-grown and encapsulated layers in the bilayer system, were examined by a combination of microscopic and scattering methods. The increase in the thickness of the deposited Pt film brought three competitive phenomena into occurrence, such as 3D–2D morphological transition, dewetting, and hillock formation. The degree of coverage, film continuity, and the crystal quality of the Pt film were significantly improved by increasing the deposition time. An optimum Pt film thickness of 70 nm was found to be suitable for obtaining a hillock-free Pt bottom electrode which also withstood the dewetting phenomena revealed during the subsequent growth of capping layers. This achievement is crucial for the deposition of functional bottom electrodes in ferroelectric and multiferroic heterostructure systems. [ABSTRACT FROM AUTHOR]

The objective of the present investigation is to optimize the thickness of Pulse Laser Deposition (PLD)-grown CoFe thin films to achieve minimal effective Gilbert damping (αeff) for potential spintronics applications. The effect of the thickness (5-30 nm) of CoFe ultra-thin films on the Si/SiO2 substrate on the structural, morphological and magnetic properties has been reported. The X-ray diffraction (XRD) peak at 44.5° shows the growth of CoFe along the (110) crystal plane. A nearly square M-H loop with high saturation magnetization (Ms) suggests good crystalline growth of CoFe film. A high coercive field (Hc) observed in the thinnest 5 nm film is due to defects such as dislocations and stacking faults that appear at very low thickness. These defects gradually decrease with an increase in CoFe film thickness, as evident from a decrease in the Hc and an increase in the Ms. The value of αeff is largest for the thinnest 5 nm film due to defects and magnetic inhomogeneities present at this thickness. The damping is reduced by approximately one-third for the 10 nm thin film in comparison to the 5 nm film, which signifies a good quality film with fewer disorders. [ABSTRACT FROM AUTHOR]

Superconducting Transition Edge Sensors employed in X-ray astrophysics space missions were realized and fully characterized in the Low temperature detector laboratory at UniGe. Several samples of Ir and Ir/Au bilayer films were grown by pulsed laser deposition at different deposition rate, varying thickness and resulting variability in critical temperature (Tc) was observed. In particular, we noticed two classes of films having discrete critical temperature (Tc), one at about the critical temperature of the bulk Ir and one at around 1.6 times compared to the bulk. Structural characterization was made and interesting correlation between critical temperature (Tc) and deposition conditions were found. Detailed X-Ray Diffraction investigations suggest a possible explanation of this effect with a clear correlation between microstrain value, grain size, and critical temperatures of the films. The study has been carried out to optimize the specified conditions to grow the film under which it is possible to accurately predict the critical temperature (Tc) by analyzing the X-ray diffraction patterns of Ir/Au films. [ABSTRACT FROM AUTHOR]

Er-doped ZnO (Zn (1-x) Er (x) O) films with (002) preferential orientated wurtzite structure were fabricated on a c-plane sapphire substrate by pulsed laser deposition (PLD). The effects of Er composition, oxygen pressure during growth, and post-growth annealing on the films' structural, electrical, and optical properties were studied by employing a comprehensive spectroscopic approach. Er-doped ZnO films with a resistivity of 4 × 10−4 Ωcm, electron conductivity n+∼1021 cm−3, and high optical transmittance (>90%) were disclosed to be appropriate candidates for transparent conducting electrode applications. A shallow donor is reported to be associated with the Er Zn defect, which is optically inactive. Er-doped ZnO samples grown with high Er composition and oxygen pressure don't show n+ conductivity because of the formation of an O-rich Er Zn -related compensating defect. Annealing at 750 °C converts the Er Zn shallow donor to another defect configuration, which is optically active for intra-4f-shell transition emissions, but no longer a shallow donor. The growth condition for maximizing the intra-4f-shell transition emission was also obtained. [ABSTRACT FROM AUTHOR]

Large temperature gradients inherent to additive manufacturing (AM) processes induce large residual stress (RS) in the final part. Because RS can influence the tribological properties, this study focuses on the relationship between wear sliding properties and RS in IN718 coatings. Such coatings were deposited with a Laser metal deposition (LMD) machine using two different scanning strategies. The wear resistance and RS state were investigated after surface milling. RS were measured before and after wear tests on a reciprocating sliding test apparatus. Two different X-ray diffraction techniques were employed to measure the surface and subsurface state RS: Laboratory Energy Dispersive X-ray Diffraction (LEDXD) and Synchrotron X-ray Energy Dispersive Diffraction (SXEDD). Due to the milling process, the coatings show similar depth distributions of RS from 22 to 92 µm depth, but exhibit different magnitudes depending on the scanning strategy used. Reciprocating sliding wear tests induced high compressive residual stresses that erased the initial RS state, and a similar wear behavior was observed in the two samples. These samples possess similar texture and grain morphology. This demonstrates that the influence of RS on wear resistance is a second-order effect. Nevertheless, it was observed that RS can still impact the wear performance at the early testing stages of the repaired parts. [ABSTRACT FROM AUTHOR]

This research deals with the effect of gallium oxide and cerium oxide as dopants on the structural and optical characteristics of tin oxide. Gallium and cerium oxide doped tin oxide was prepared with different doping concentrations (0, 0.03, 0.05 and 0.07) wt. pure and doped tin oxide thin films were prepared by the pulsed laser deposition technique. X-ray diffraction and UV-Visible spectrophotometer were employed to investigate both oxides doping effects. Results showed that all prepared samples have poly-crystalline structure with a preferred plane of crystal growth along (110), where the crystal size grew from 40.3 nm to 64.5 nm and to 43.5 nm for Ga2O3 and CeO2 doped tin oxide thin films, respectively. Transmittance decreased drastically by increasing the doping ratio of gallium oxide. In contrast, it increased by increasing the doping ratio of cerium oxide. The optical energy gap was found to change in nonsystematic sequence with the increase of Ga2O3 doping concentration, while it decreased monotonically by increasing the CeO2 doping concentration. [ABSTRACT FROM AUTHOR]

Ferroelectricity is demonstrated for the first time in Si(100)/SiO2/TiN/HfO2-ZrO2/TiN stack using pulsed laser deposition (PLD) and the effects of temperatures, partial oxygen pressures, and thickness for the stabilization of the ferroelectric phase were mapped. Thin films deposited at a higher temperature and a higher oxygen partial pressure have a higher thickness, demonstrating a better ferroelectric response with ~12 µC/cm² remnant polarization, a leakage current of 10-7 A (at 8 V) and endurance >1011 cycles indicative of an orthorhombic crystal phase. In contrast, thin films deposited at lower temperatures and pressures does not exhibit ferroelectric behavior. These films can be attributed to having a dominant monoclinic phase, having lower grain size and increased leakage current. Finally, the effects of ZrO2 as top and bottom layer were also investigated which showed that ZrO2 as the top layer provided better mechanical confinement for stabilizing the orthorhombic phase instead of as the bottom layer. [ABSTRACT FROM AUTHOR]

In this work, the effects of glass and Si polycrystalline substrates on structural, morphological, optical and electrical properties of zinc oxide thin films (ZnO) deposited at 450°C by pulsed laser deposition technique (PLD) have been investigated. KrF excimer laser (248 nm, 25 ns, 5 Hz, 2 J/cm2) was used as a source. X-ray diffraction patterns showed that ZnO thin films have been crystallized in hexagonal wurtzite-type structure with a preferred (002) orientation. Highly c-axis preferred orientation, which is critical for piezoelectric applications. The grain sizes calculated from X ray diffraction (XRD) patterns varies from 37 to 22 nm. All the films have a good surface morphology. Optical waveguiding properties of the films were characterized by using prism-coupling method. The distinct M-lines of the guided transverse magnetic (TM) and transverse electric (TE) modes of the ZnO films waveguide have been observed. In the aim to study the optical properties of the ZnO films, an accurate refractive index and thickness measurement apparatus was set up, which is called M-lines device. An evaluation of experimental uncertainty and calculation of the precision of the refractive index and thickness were developed on the ZnO films. The optical transmittance spectra showed good transparency in the visible region. Optical band gap calculated equal to 3.22 eV. [ABSTRACT FROM AUTHOR]

In order to create CdO TCO's films, a pulsed laser (Nd: YAG) was utilized to ablate the target of CdO in the active environment with low oxygen pressure. The optimal substrate temperature was reached in this work by using pulsed laser deposition (PLD) to build cadmium oxide (CdO) nano-films at different substrate temperatures of 200, 300, and 400oC. The CdO target was exposed to a pulsed laser with energy of 1800 mJ at a standard wavelength of 1064 nm, pulse duration of 10 ns, and ablating CdO nano-grains on quartz substrates. The XRD result shows three main planes (111), (200), and (220), and also shows increase in the intensity of the peak for the plane of (111) at the space of the atomic of 2.744Å, where the XRD results shows, an increased in the crystallization with the increased the substrate temperatures. The morphological images show the best preparation condition at 300oC that are the average grain size of roughly 82.4 nm, and surface roughness accumulated to around 1.14 nm. The morphological and structural characteristics of the prepared nano-films are tested and examined at various substrate temperatures. The findings showed that the substrate temperatures were associated with a greater crystenality. [ABSTRACT FROM AUTHOR]

The goal of this investigation is to prepare zinc oxide (ZnO) nano-thin films by pulsed laser deposition (PLD) technique through Q-switching double frequency Nd:YAG laser (532 nm) wavelength, pulse frequency 6 Hz, and 300 mJ energy under vacuum conditions (10-3 torr) at room temperature. (ZnO) nano-thin films were deposited on glass substrates with different thickness of 300, 600 and 900 nm. ZnO films, were then annealed in air at a temperature of 500 °C for one hour. The results were compared with the researchers' previous theoretical study. The XRD analysis of ZnO nano-thin films indicated a hexagonal multi-crystalline wurtzite structure with preferential growth lines (100), (002), (101) for ZnO nano-thin films with different thicknesses of un-annealed samples and after annealing. While the UV-Visible spectrum manifested that the ZnO has a high absorption at UV range and wide energy gap values of (3.4, 3.42, and 3.46 eV) for the three thicknesses. The surface topography of the films evinced a rough surface which increased with increasing thickness, whereas the grain size decreased, and the average grain size was about 56.68 nm. Furthermore, the nano-thin films showed a granular morphology with a tendency to form smaller particles with increasing thickness. [ABSTRACT FROM AUTHOR]

We prepared a stacked structure consisting of a quasi-free-standing functional oxide thin film and a ceramic piezoelectric disk and observed the effect of the piezoelectric disk deformation on the resistance of the thin film. Epitaxial V2O3 films were grown by a pulsed laser deposition method on muscovite mica substrates, peeled off using Scotch tapes, and transferred onto piezoelectric elements. In this V2O3/insulator/top electrode/piezoelectronic disk/bottom electrode structure, the resistance of the V2O3 film displayed a variation of 60% by sweeping the piezoelectronic disk bias. With support from x-ray diffraction measurements under an electric field, a huge gauge factor of 3 × 103 in the V2O3 film was inferred. The sizeable resistance change in the V2O3 layer is ascribed to the piezo-actuated evolution of c/a ratios, which drives the material towards an insulating phase. A memory effect on the resistance, related to the hysteretic displacement of the piezoelectric material, is also presented. [ABSTRACT FROM AUTHOR]

We have deposited LaNiO3 thin films on LaAlO3 (001), SrTiO3 (001), and Si (001) substrates using the pulsed laser deposition technique. Depositions were carried out at various substrate temperatures ranging from 0 to 800 °C. The effects of lattice mismatch and structural disorder on the transport properties of films deposited on various substrates and at different substrate temperatures are reported. X-ray diffraction confirms a highly c-axis oriented growth of LaNiO3 films on all the substrates at substrate temperatures of 600 and 800 °C, while at lower substrate temperatures deposited films are amorphous. Emergence of a new Raman mode indicates symmetry lowering in all the deposited crystalline films. Hardening of the Eg(3) (∼400 cm−1) mode is also observed with the rise of in-plane compressive strain. Resistivity curves for films on Si show a semiconducting behaviour and follow a variable range hopping mechanism. Crystalline films on LaAlO3 and SrTiO3 exhibit a metallic character along with a low-temperature resistivity upturn, which is attributed to the contribution of self-localization to resistivity at low temperatures as indicated by magnetotransport measurements. [ABSTRACT FROM AUTHOR]

An antipolar phase is confirmed for NaNbO3 thin films grown by pulsed laser deposition on SrTiO3 (100) substrates. Reciprocal space maps and transmission electron microscopy reveal the presence of characteristic 1/4 superlattice reflections, indicative of the antipolar displacement of Na and Nb-ions. Furthermore, x-ray diffraction unveils the presence of two different orientations of the same phase for thin films beyond a critical thickness of about 60 nm. This orientation change with increasing thickness can be explained as an extraordinary strain compensation mechanism, changing magnitude and sign of the strain at the same time. The polarization vs electric field behavior exposes a characteristic thickness dependence, with the antiferroelectric phase stabilized for very thin films and a field induced ferroelectric hysteresis for a film of 310 nm having a maximum polarization of 26.5 μC cm − 2 , which is among the highest values reported for NaNbO3 thin films grown on SrTiO3 (100). [ABSTRACT FROM AUTHOR]

Epitaxial thin films of cobalt ferrite (CoFe2O4) are grown on two isostructural substrates, (001)-oriented MgGa2O4 and ZnGa2O4, using pulsed laser deposition. The substrates have a lattice mismatch of 1.26% and 0.70% with bulk CoFe2O4 (CFO) crystal. We have systematically investigated the structural and magnetic properties of the epitaxial CFO films on these substrates. X-ray diffraction and transmission electron microscopy result analysis reveal that the films deposited on spinel ZnGa2O4 are essentially free of defects and are under a small compressive strain, while films on MgGa2O4 show partial strain relaxation along with defect formation. Room temperature magnetization data indicate that CFO grown on ZnGa2O4 substrates have a bulk-like saturation magnetization of 420 emu/cc and a uniaxial substrate-induced anisotropy value of − 22.9 × 10 6 erg/cm3 with an anisotropy field as low as 60 kOe. [ABSTRACT FROM AUTHOR]

In this study, we report on the fabrication of polycrystalline thin film Bi 2 SiO 5 , a notable non-perovskite ferroelectric material. The thin films were deposited on Pt-covered Si substrates by pulsed laser deposition (PLD) at room temperature, followed by a post-annealing process in air. The as-deposited thin film was of an amorphous phase of Bi-Si-O, and turned to a polycrystalline phase of Bi 2 SiO 5 by the post-annealing above 550°C. The influences of the post-annealing temperature on the phase preference, surface morphology, and dielectric properties of the thin films were investigated by Raman spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM), and dielectric measurements. As a result, the optimal post-annealing temperature was determined to be 600°C, yielding a good ferroelectric polycrystalline Bi 2 SiO 5 thin film with a relative dielectric constant of 143 and a remanent polarization (2 P r) of 7.2 μC cm−2. • Polycrystalline Bi 2 SiO 5 thin films fabricated by PLD with post-annealing. • As-deposited amorphous Bi-Si-O thin films crystalized by post-annealing above 550 °C. • Post-annealing temperature affects crystallization, roughness, and dielectric properties. • Remanent polarization (2 P r) of 7.2 μC cm−2 was obtained by post-annealing at 600 °C. [ABSTRACT FROM AUTHOR]

Artificial (BiFeO3)0.5Λ/(LaFeO3)0.5Λ superlattices have been grown by pulsed laser deposition. The periodicity Λ was varied from 150 Å to 25 Å and the relative ratio between BiFeO3 (BFO) and LaFeO3 (LFO) is kept constant in each period. X-ray diffraction, transmission electron microscopy, and Raman spectroscopy investigations indicate antiferroelectric-like structures for large periodicity (Λ ≥ 76 Å), while Pnma LaFeO3-like structures are observed for small periodicity Λ ≤ 50 Å. Room temperature magnetic measurements were obtained by vibrating sample magnetometry and suggest antiferromagnetic ordering with weak ferromagnetism. Temperature dependent x-ray diffraction studies show an important shift of paraelectric-antiferroelectric phase transition scaling with BFO thickness. Strain and size effects explain this behavior and discussion is also made on the possible role of the oxygen octahedral rotation/tilt degree of freedom. [ABSTRACT FROM AUTHOR]

Yttrium iron garnet (YIG:Y3Fe5O12) thin films were grown on (111) gadolinium gallium garnet (Gd3Ga5O12, GGG) substrates using pulsed-laser deposition under several different deposition and annealing conditions. X-ray diffraction measurements revealed that the crystallographical orientation of the YIG films is pseudomorphic to and the same as that of the GGG substrate, with a slight rhombohedral distortion along the surface normal. Furthermore, X-ray reciprocal space mapping evidenced that in-situ annealed YIG films during film growth are under compressive strain, whereas ex-situ annealed films have two different regions under compressive and tensile strain. The saturation magnetization ( 4 π M S ) of the films was found to vary, according to the deposition conditions, within the range of 1350 to 1740 G, with a very low coercivity of H C < 5 Oe. From ferromagnetic resonance (FMR) measurements, we estimated the effective saturation magnetization ( 4 π M e f f ) to be 1810 to 2530 G, which are larger than that of single crystalline bulk YIG (∼1750 G). Such high values of 4 π M e f f are attributable to the negative anisotropy field ( H U ) that increases in size with increasing compressive in-plane strain induced in YIG films. The damping constant ( α G ) of the grown YIG films was found to be quite sensitive to the strain employed. The lowest value of α G obtained was 2.8 × 10−4 for the case of negligible strain. These results suggest a means of tailoring H U and α G in the grown YIG films by the engineering of strain for applications in spintronics and magneto-optical devices. [ABSTRACT FROM AUTHOR]

The gradual and uniform variation in the composition of the material, generally two, is called functionally graded materials (FGM). These FGM are used in practical applications to advantage both material properties. Several methods are used to fabricate the FGM components. The current article is research on the direct energy dispersive technique of 3D Printing employed for depositing the SS316L and Co-Cr-Mo alloy FGM samples. L9 orthogonal array of Taguchi method is used. Process parameters like laser power, powder feed rate and scan speed have been used for deposition. Their structural properties are analysed using scanning electron microscopy, X-ray diffraction, element dispersive technique, and Fourier transform impedance spectroscopy. The results reveal that defect-free samples were deposited, and all the samples have Body Centered Cubic structure except one. Good elemental bonding was observed between SS316L and Co-Cr-Mo alloy. [ABSTRACT FROM AUTHOR]

Composition spread Mn-doped Ba 0.6 Sr 0.4 Ti 1- x Mn x O 3 (BSTM x , 0 ≤ x ≤ 0.05) thin films were prepared on La 0.7 Sr 0.3 MnO 3 /SrTiO 3 (LSMO/STO) layer by combinatorial pulsed laser deposition. When x is less than 3.3%, the BSTM x films are single phase according to X-ray diffraction data, and the Au/BSTM x /LSMO structure presents asymmetric transport properties. The asymmetry of the transport property gets weak with increasing Mn doping concentration. The reverse-bias current density of the Au/BSTM x /LSMO structure remains at a low value of 10−7 A/cm2, and the forward-bias current density reduces rapidly with the ascending doping content (x ≤ 1.8%). Further increasing the Mn content, the differences between the positive and reverse current densities become smaller, and almost vanish when the Mn content is greater than 3.8%, indicating the disappearance of the asymmetry of the transport property. The effects of the LSMO electrode, Au/BSTM x Schottky junction, BSTM x thin film, and BSTM x /LSMO interface on the whole electrical transport properties are discussed by virtue of the experimental and fitted impedance spectrums. Our results are helpful for insight into the doping mechanisms in perovskite oxides. [ABSTRACT FROM AUTHOR]

Compounds from ZnO doped with AgO in different ratio (0,3,5,7, and 9)wt.% were prepared.Thin films from the prepared compounds were deposited on a glass substrate using the pulsed laser deposition method. The XRD pattern confirmed the presence of a single-phase hexagonal wurtzite ZnO structure, without the presence of a secondary phase. AFM measurements showed an increase in both average grain size and average surface roughness with increasing concentration content of (AgO).The crystallite size of ZnO of the main peak corresponding to the preferred plane of crystal growth named (100) increases from 17.8 to 22.5nm by increasing of AgO doping ratio from 0 to 9%. The absorbance and transmittance in the wavelength range (350-1100 nm) were used to determine the optical properties. The results showed that the optical energy gap for direct allowed transition (r =0.5 )are (3.21, 3.2,3.15, 3.15, 2.95 ) Ev, respectively. The optical constants were also measured as a function of wavelength. This optical measurements showed the prepared thin film have many applications for solar cell fabrication and sensing devices. [ABSTRACT FROM AUTHOR]

Hf (1- x) Y x O 2 (x = 0, 0.10, 0.15, 0.20) epitaxial thin films on YSZ(100) substrate were prepared at different oxygen (O 2) partial pressures (100, 70, 30, and 10 sccm) by pulsed laser deposition. The effect of oxygen partial pressure on crystalline and local structure was investigated using X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and X-ray absorption spectroscopy (XAS). The surface composition was determined by X-ray photoelectron spectroscopy. The XRD and FTIR studies reveal that undoped HfO 2 thin films remain in monoclinic phase, and the Hf 0.85 Y 0.15 O 2 & Hf 0.80 Y 0.20 O 2 films stabilize in cubic phase at all oxygen pressures, whereas the structure of Hf 0.90 Y 0.10 O 2 films changes from orthorhombic to cubic as oxygen pressure reduces from 100 sccm. The XAS at Hf-L 3 edge and O K-edge shows the changes in bond distances, disorder and hybridization. In monoclinic HfO 2 films the Hf–O bond distance and disorder increases and Hf–Hf bond decreases as the O 2 partial pressure decreases, whereas disorder in doped films shows anomalous behaviour. The oxygen vacancies are evident from both XAS and photoluminescence studies. The results enlighten a deeper understanding of phase change, local structure, optical properties and pave a way to stabilize and identify different technologically important HfO 2 phases for dielectric and ferroelectric applications. • The surface composition of thin films was calculated using XPS technique. • The spectroscopic investigation of phase transformation using FTIR and SXAS technique for Y doped HfO 2 epitaxial thin films deposited at different oxygen partial pressure. • The XRD and FTIR results show that the undoped HfO 2 film is single phase monoclinic at all oxygen partial pressures, whereas Hf 0.90 Y 0.10 O 2 crystal structure is orthorhombic at 100 sccm O 2 partial pressure and cubic at all other pressures. • Hf 0.85 Y 0.15 O 2 & Hf 0.80 Y 0.20 O 2 films remains in cubic phase at all oxygen partial pressures. • The TEM results show epitaxial nature of film, and support the XRD, FTIR and XPS result. • The soft X-ray absorption spectroscopic (SXAS) results confirm the modification in the local electronic structure because of change in crystal structure as well as oxygen partial pressure. • The extended x-ray absorption fine structure (EXAFS) results show that the bond distance and local structure disorder are dependent upon the crystal phase as well as on the oxygen partial pressure. • The photoluminescence areal intensity shows strong dependence on local structure disorder. [ABSTRACT FROM AUTHOR]

We investigate the structural properties of Fe 1 − x Ni x /Cu/Fe 1 − x Ni x (x=0.5, non-Invar and x=0.36, Invar) trilayers deposited on Si(100) at room temperature using the dc magnetron sputtering technique in ultra high vacuum conditions taking high-purity Fe, Ni and Cu metals with Cu layer thickness 4, 6 and 8 nm for each alloy composition. The structure of the alloy films of the trilayers was investigated using x-ray diffraction and the thickness and roughness of the layers were obtained by x-ray reflectivity measurement. Both the as-prepared and annealed trilayers exhibit layered structure. The as-deposited Fe–Ni alloy in non-Invar trilayer exhibits only the fcc structure. whereas in the Invar alloy it exhibits a mixed fcc and bcc phases. Interestingly after annealing at 425 ∘ C in ultra high vacuum, the Invar alloy completely transformed to the fcc structure for all Cu thicknesses. In both Invar and non-Invar trilayers, the Bragg reflections corresponding to Fe–Ni alloy layers become sharp after annealing. The induced structural transformation in the Invar trilayer is explained using enhanced diffusion of Fe and Ni atoms at high temperatures. [ABSTRACT FROM AUTHOR]

Superlattice (SL) structures of Ba2FeMoO6/Ba0.5Sr0.5TiO3 were grown via pulsed laser deposition on high quality ultra-smooth SrTiO3 substrates. N number of ferroelectric Ba0.5Sr0.5TiO3 layers were grown on five layers of ferromagnetic Ba2FeMoO6 and their structural, magnetic, transport, and magneto-transport properties were examined, focusing on the effects of superlattice periodicity of Ba0.5Sr0.5TiO3 layers. XRD analysis of SLs proved their layered superlattice structure. Magnetic study of the SLs showed increment of saturation magnetization and decrease of Curie temperature when compared to magnetization of pure Ba2FeMoO6 thin film. Magneto-transport measurement showed the presence of negative magneto-resistance in all superlattice samples, similar to magneto-transport behavior of pure Ba2FeMoO6 thin film. Hall measurement and transport study showed a consistent increment of anomalous Hall effect and temperature dependent conductivity, respectively, with the number of Ba0.5Sr0.5TiO3 layers. [ABSTRACT FROM AUTHOR]

High quality epitaxial Ba2FeMoO6thin films and Ba2FeMoO6-(BaxSr1-x)TiO3 bi-layer (BL) and superlattice(SL)structures were grown via pulsed laser deposition under low oxygen pressure, and their structural, magnetic, and magneto-transport properties were examined. Superlattice and bi-layer structures were confirmed by X-ray diffraction patterns. Low temperature magnetic measurement shows that the saturationmagnetization (MS) is significantly higher for SLs and almost similar or lower for BLs, when compared to phase pure Ba2FeMoO6thin films. The variation of the coercive field (HC) follows exact opposite trend, where BL samples have higher HC and SL samples have lower HC than pure Ba2FeMoO6thin films. Also, a significant decrease of the Curie temperature is found in both BL and SLstructures compared to pure Ba2FeMoO6thin films. Negative magneto-resistance is seen in all the BL and SLstructures as well as in pure Ba2FeMoO6thin films. In contrast to the magnetic properties, the magneto-transport properties do not show much variation with induced strain. [ABSTRACT FROM AUTHOR]

We report on the epitaxial growth and room-temperature ferromagnetic properties of MgO thin films deposited on hexagonal c-sapphire substrates by pulsed laser deposition. The epitaxial nature of the films has been confirmed by both θ-2θ and φ-scans of X-ray diffraction pattern. Even though bulk MgO is a nonmagnetic insulator, we have found that the MgO films exhibit ferromagnetism and hysteresis loops yielding a maximum saturation magnetization up to 17 emu/cc and large coercivity, Hc=1200 Oe. We have also found that the saturation magnetization gets enhanced and that the crystallization degraded with decreased growth temperature, suggesting that the origin of our magnetic coupling could be point defects manifested by the strain in the films. X-ray (θ-2θ) diffraction peak shift and strain analysis clearly support the presence of strain in films resulting from the presence of point defects. Based on careful investigations using secondary ion mass spectrometer and X-ray photoelectron spectroscopy studies, we have ruled out the possibility of the presence of any external magnetic impurities. We discuss the critical role of microstructural characteristics and associated strain on the physical properties of the MgO films and establish a correlation between defects and magnetic properties. [ABSTRACT FROM AUTHOR]

Chromium oxide (Cr2O3) doped ZnO nanoparticles were prepared by pulsed laser deposition (PLD) technique at different concentration ratios (0, 3, 5, 7 and 9 wt %) of ZnO on glass substrate. The effects of ZnO dopant on the average crystallite size of the synthesized nanoparticles was examined By X-ray diffraction. The morphological features were detected using atomic force microscopy (AFM). The optical band gap value was observed to range between 2.78 to 2.50 eV by UV-Vis absorption spectroscopy, with longer wavelength shifted in comparison with that of the bulk Cr2O3 (~3eV). Gas sensitivity, response, and recovery times of the sensor in the presence of NH3 gas were studied and discussed. In the present work, we found that the sensitivity was increased upon increasing the concentration ratio from 3 to 5%wt of ZnO, whereas it was decreased again over that value. Also, we found that the sensitivity was increased when increasing operating temperature, while the response time was decreased. The optimum concentrations ratio for NH3 gas sensitivity at 5%wt ZnO revealed sensitivity of 66.67% and response time of 14s at operating temperature of 300oC and 700mJ PLD energy. [ABSTRACT FROM AUTHOR]

ZnO-SnO2 composite thin films have been deposited at 400 °C on glass substrates using targets of different SnO2 content (1 to 40 wt. %) by pulsed laser deposition technique. The structural, optical, and electrical properties of the composite films have been studied as a function of SnO2 content. It is revealed from X-ray diffraction analysis that films are crystalline in nature and the crystallite size decreases from 20-23 nm to 5-7 nm with increase of SnO2 content. X-ray photoelectron spectroscopy analysis indicates that Sn is predominantly doped into the ZnO lattice upto a SnO2 content of 15 wt. % in the composite. For higher concentration, a separate SnO2 phase is segregated in the composite. The band gap energy as well as the electrical conductivity can be tuned by varying the SnO2 content in the composite. Low temperature electrical conductivity measurements show three dominant conduction mechanisms in the temperature range of 20-300K. At high temperature range of 200-300 K, thermal activation conduction process is dominant. Nearest neighbor hopping conduction mechanism, which occurs in the shallow impurity bands, is dominant in the temperature range of 90-200K. In the low temperature range of 20-90 K, the electronic transport occurs through Mott's variable range hopping conduction process. [ABSTRACT FROM AUTHOR]

Growth of pure phase delafossite CuFeO2 thin films on Al2O3 (00.1) substrates by pulsed laser deposition was systematically investigated as a function of growth temperature and oxygen pressure. X-ray diffraction, transmission electron microscopy, Raman scattering, and x-ray absorption spectroscopy confirmed the existence of the delafossite phase. Infrared reflectivity spectra determined a band edge at 1.15?eV, in agreement with the bulk delafossite data. Magnetization measurements on CuFeO2 films demonstrated a phase transition at TC ≈ 15 ± 1?K, which agrees with the first antiferromagnetic transition at 14?K in the bulk CuFeO2. Low temperature magnetic phase is best described by commensurate, weak ferromagnetic spin ordering along the c-axis. [ABSTRACT FROM AUTHOR]

We have investigated the origin of superstructure peaks as observed by X-ray diffraction of multiferroic Bi(Fe0.5Cr0.5)O3 thin films grown by pulsed laser deposition on single crystal SrTiO3 substrates. The photon energy dependence of the contrast between the atomic scattering factors of Fe and Cr is used to rule out a chemically ordered double perovskite Bi2FeCrO6 (BFCO). Structural calculations suggest that the experimentally observed superstructure occurs due to unequal cation displacements along the pseudo-cubic [111] direction that mimic the unit cell of the chemically ordered compound. This result helps to clarify discrepancies in the correlations of structural and magnetic order reported for Bi2FeCrO6. The observation of a superstructure in itself is not a sufficient proof of chemical order in double perovskites. [ABSTRACT FROM AUTHOR]

Structural properties of rhombohedral α‐(AlxGa1−x)2O3 thin films grown by two combinatorial pulsed laser deposition (PLD) techniques are investigated for the entire composition range. One α‐(AlxGa1−x)2O3 thin film is deposited on a 2 inch in diameter large a‐plane sapphire substrate using the continuous composition spread (CCS) PLD technique to fabricate a thin film with varying Al content ranging between x = 0.13 and x = 0.84. Laterally homogeneous α‐(AlxGa1−x)2O3 thin films exhibiting discrete Al contents are fabricated using radially segmented PLD targets on (11.0) Al2O3. Independent of the PLD technique, for x ≈ 0.55, a change from relaxed to pseudomorphic growth is observed as confirmed by the evolution of in‐ and out‐of‐plane lattice constants. The crystal structure is studied depending on the cation composition by X‐ray diffraction confirming the fabrication of epitaxial, corundum‐structured thin films. [ABSTRACT FROM AUTHOR]

Pristine and Cu-doped ZnO thin films with 3 wt%, 5 wt% & 7 wt% Cu concentrations were deposited by pulsed laser deposition (PLD) to observe the effect of incorporation of Cu in ZnO lattice towards their structural, optical and electronic structural properties. Structural investigations were carried out using X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), and Field Emission Scanning Electron Microscopy (FESEM). Optical studies were performed using UV–Visible (UV–Vis), Photoluminescence, and RAMAN spectroscopies. The electronic structure of the films was studied using X-Ray absorption spectroscopy (XAS). All the films are oriented along (002) plane with wurtzite hexagonal symmetry, confirmed from XRD results. The optical band gap energy of ZnO thin films decreases from 3.26 eV to 3.0 eV with increasing Cu concentration from 0 to 7 wt% respectively. The various structural defects were confirmed from PL spectrums. The variation in the hybridization of O 2p states with Cu doping concentration is understood by XAS study. • Thin film of Cu doped ZnO and pristine ZnO deposited by pulsed laser deposition (PLD) over fused silica. • Structural studies and Optical band gap calculation ▶Defects confirmation by PL. • Raman studies for vibration of atom. • Synchrotron X-ray absorption spectroscopy for electronic structure studies. [ABSTRACT FROM AUTHOR]

Sr2FeMoO6 (SFMO) films were grown on SrTiO3 (100)- and (111)-oriented substrates via pulsed laser deposition (PLD). In order to study the fundamental characteristics of deposition, films were grown in two different PLD chambers. In chamber I, the best films were grown with a relatively long substrate-to-target distance (89 mm), high substrate temperature (850 °C), and low pressure (50 mTorr) in a 95% Ar/5% H2 atmosphere. Although X-ray diffraction (XRD) measurements indicate these films are single phase, Rutherford Backscattering (RBS) measurements reveal considerable non-stoichiometry, corresponding to a Sr2+yFe1+xMo1-xO6 composition with x≅0.2-0.3. This level of non-stoichiometry results in inferior magnetic properties. In chamber II, the best films were grown with a much shorter substrate-to-target distance (38 mm), lower temperature (680 °C), and higher pressure (225 mTorr). XRD measurements show that the films are single phase, and RBS measurements indicate that they are nearly stoichiometric. The degree of ordering between Fe and Mo was dependent on both the temperature and pressure used during deposition, reaching a maximum order parameter of 85%. The saturation magnetization increases as the Fe/Mo ordering increases, reaching a maximum of 2.4 μB/f.u. Based on prior studies of bulk samples, one would expect a higher saturation magnetization for this degree of Fe/Mo order. The presence of extra strontium oxide layers in the form of Ruddlesden-Popper intergrowths appears to be responsible for the lower than expected saturation magnetization of these films. [ABSTRACT FROM AUTHOR]

Pulsed laser deposition was employed to deposit epitaxial Ge2Sb2Te5-layers (GST) on (100) oriented KCl-substrates. XRD-measurements show a process temperature window for epitaxial growth of the cubic phase between 200 and 300 °C. Below 250 °C (111) oriented GST dominates the growth process and above 250 °C the (100) orientation is the dominating one. Pole figure measurements confirm these results and additionally reveal that the (111) orientation consists of 4 domains with 90° azimuthal separation with an initial 15° rotation with the substrate lattice, i.e., [2-1-1]GST ∥ [100]KCl. The (100) orientation grows cube-on-cube with KCl. A systematic variation of the deposition rate showed that it is possible to obtain epitaxial films in the range between 2.5 and 250 nm/min with no significant deterioration of crystal quality. A smooth topography of (111) oriented films was found, whereas the (100) dominated films in general show higher surface roughness as evidenced from atomic force microscopy investigations. [ABSTRACT FROM AUTHOR]

We fabricated SrRuO3/BaTiO3/GdScO3 heterostructures in which the BaTiO3 layer is one unit cell thick by pulsed laser deposition and elucidated how the BaTiO3 layer influences structural and magneto-transport properties of the SrRuO3 layer through octahedral connections across the heterointerface. Our X-ray-diffraction-based structural characterizations show that while an epitaxial SrRuO3 layer grown directly on a GdScO3 substrate is in the monoclinic phase with RuO6 octahedral tilts, a one-unit-cell-thick BaTiO3 layer inserted between SrRuO3 and GdScO3 stabilizes the tetragonal SrRuO3 layer with largely reduced RuO6 tilts. Our high-angle annular dark-field and annular bright-field scanning transmission electron microscopy observations provide an atomic-level view of the octahedral connections across the heterostructure and reveal that the BaTiO3 layer only one unit cell thick is thick enough to stabilize the RuO6-TiO6 octahedral connections with negligible in-plane oxygen atomic displacements. This results in no octahedral tilts propagating into the SrRuO3 layer and leads to the formation of a tetragonal SrRuO3 layer. The magneto-transport property characterizations also reveal a strong impact of the octahedral connections modified by the inserted BaTiO3 layer on the spin-orbit interaction of the SrRuO3 layer. The SrRuO3 layer on BaTiO3/ GdScO3 has in-plane magnetic anisotropy. This is in contrast to the magnetic anisotropy of the monoclinic SrRuO3 films on the GdScO3 substrate, in which the easy axis is ~45° to the film surface normal. Our results demonstrate that the one-unit-cell-thick layer of BaTiO3 can control and manipulate the interfacial octahedral connection closely linked to the structure-property relationship of heterostructures. [ABSTRACT FROM AUTHOR]

We report on the ferroelectricity for morphotropic-phase-boundary lead (Pb) free 0.5BaTi0.8Zr0.2 O3-0.5Ba0.7Ca0.3TiO3 (0.5BZT-0.5BCT) thin films. Thin films were grown on Pt/Ti/SiO2/Si substrate using pulsed laser deposition. Raman spectroscopic data combined with the X-ray diffraction analyses confirm body centered tetragonal crystallographic structure 0.5BZT-0.5 BCT thin films on Pt/Ti/SiO2/Si. Polarization studies demonstrate that these 0.5BZT-0.5BCT films exhibit a large remnant and saturation polarization of 37 μC/cm2 and 40 μC/cm2, respectively, with a coercive field of 140 kV/cm. A correlation between polarization dynamics, structural distortion, and phonon vibration is established. The splitting of X-ray diffraction peak of the thin film in the 2θ range of 44.5° to 46.5° represents high degree of tetragonality. The tetragonality factor calculated by Rietveld analysis was found to be 0.006 and can be a major cause for the increased remnant polarization value. It is established from Raman spectra that the non-centrosymmetricity due to the displacement of Ti/Zr ions from its octahedral position is related to the peak position as well as the broadening of the A1 (LO) optical phonon mode. This increase of broadness in the thin film causes an increase in the dipole moment of the unit cell and, hence, the net increase in polarization values. [ABSTRACT FROM AUTHOR]

Advanced and innovative solutions are currently under investigations in order to solve the long-standing issues of materials constituting the breeding blanket of a future fusion reactor. Tritium permeation through steels, corrosion perpetrated by the breeding media, magnetohydrodynamic (MHD) effects and intense neutron irradiation hinder the realization of this technology. Recently, the employment of protective nanoceramic coatings has been considered as one of the few viable solutions. In particular, the pulsed laser deposition (PLD) technique allows to produce dense, compact and uniform coatings, which are the fundamental characteristics when designing a protective barrier. Yttrium oxide (Y2O3) is one of the most promising candidates given its superior stability when facing lithium-based heavy liquid metals and also its low nuclear activation yield, thus it was selected as subject of study and characterzation. PLD-grown Y2O3 coatings were then tested in order to assess their feasability as protective barriers at blanket relevant conditions. Basic characterization of the as deposited and annealed (450 °C) films was perfomed (scanning electron microscopy, atomic force microscope, grazing incident angle x-rays diffraction, nanoindenation). A coated sample was also exposed to static Pb-16Li at.% for 1000 h, showing optimal corrosion resistance and thermal stability at high temperature (550 °C). Finally, the electrical resistivity of this material was measured (up to 200 °C) in order to evaluate its ability to mitigate the MHD detrimental effects. To conclude, a preliminary characterization of the PLD-grown Y2O3 coatings proved the possibility to employ them as multifunctional protective barrier to enable the accomplishment of the breeding blanket technology. [ABSTRACT FROM AUTHOR]

Dielectric barium strontium titanate films were deposited on MgO (001) substrate by pulsed‐laser deposition (PLD) and monitored in situ by means of reflection high‐energy electron diffraction and time‐resolved X‐ray diffraction (TRXRD). TRXRD showed two growth periods of the BSTO film and a transformation in the crystalline structure was detected as the thickness exceeds 80 nm. The occurrence of two different crystalline regions, namely BSTO1 and BSTO2 was proved by X‐ray diffraction (XRD). Ex situ transmission electron microscopy (TEM) techniques, including diffraction‐contrast as well as high‐resolution TEM, nanobeam electron diffraction, and scanning TEM in combination with energy‐dispersive X‐ray spectroscopy reveal structural and microchemical peculiarities of the BSTO film. By these TEM analyses, the presence of the two different regions BSTO1 and BSTO2 within the PLD‐grown BSTO layer was demonstrated. Regions of phase BSTO2 were found on top of nanoscaled MgO islands formed on the substrate surface during annealing at high temperature. While the majority phase BSTO1 has a single‐crystalline structure over wide ranges, BSTO2 regions seem to be poly‐ or even nanocrystalline, and the chemical composition of the two phases is also different. The transition in the growth periods is presumably related to the occurrence of BSTO2 regions during layer growth. [ABSTRACT FROM AUTHOR]

We report on the study of epitaxial MgO thin films on (0001) Al-doped ZnO (Al: ZnO) underlayers, grown by oxygen plasma assisted pulsed laser deposition technique. A systematic investigation of the MgO thin films was performed by X-ray diffraction and atomic force microscopy, along with the current-voltage characteristics. A distinguished behavior was observed that the preferred MgO orientation changes from (111) to (001) in the films as the growth temperature increases. Two completely different in-plane epitaxial relationships were also determined from X-ray diffraction as: [110]MgO//[[formula]]Al: ZnO and [110]MgO//[[formula]]Al: ZnO for (001) MgO with 60° rotated triplet domains, and [110]MgO//[[formula]]Al: ZnO for (111) MgO with 180° rotated twin. The pronounced temperature dependence indicates a reconciliation of the nucleation driving forces among surface, interfacial, and strain energy for heteroepitaxy of cubic MgO on hexagonal Al: ZnO. The related interfacial atomic registry is considered to be important to the formation of unusual (001) MgO on hexagonal crystals. In addition, the electrical characterization revealed a dramatic reduction of the leakage current in (001) MgO thin films, whereas the small grain size of (111) MgO is identified by atomic force microscopy as a main cause of large leakage current. [ABSTRACT FROM AUTHOR]

The cross-plane thermoelectric transport properties of La0.67Sr0.33MnO3 (LSMO)/LaMnO3 (LMO) oxide metal/semiconductor superlattices were investigated. The LSMO and LMO thin-film depositions were performed using pulsed laser deposition to achieve low resistivity constituent materials for LSMO/LMO superlattice heterostructures on (100)-strontium titanate substrates. X-ray diffraction and high-resolution reciprocal space mapping indicate that the superlattices are epitaxial and pseudomorphic. Cross-plane devices were fabricated by etching cylindrical pillar structures in superlattices using inductively, this coupled-plasma reactive-ion etching. The cross-plane electrical conductivity data for LSMO/LMO superlattices reveal a lowering of the effective barrier height to 223 meV as well as an increase in cross-plane conductivity by an order of magnitude compared to high resistivity superlattices. These results suggest that controlling the oxygen deficiency in the constituent materials enables modification of the effective barrier height and increases the cross-plane conductivity in oxide superlattices. The cross-plane LSMO/LMO superlattices showed a giant Seebeck coefficient of 2560 μV/K at 300 K that increases to 16 640 μV/K at 360 K. The giant increase in the Seebeck coefficient with temperature may include a collective contribution from the interplay of charge, spin current, and phonon drag. The low resistance oxide superlattices exhibited a room temperature cross-plane thermal conductivity of 0.92 W/m K, this indicating that the suppression of thermal conductivities due to the interfaces is preserved in both low and high resistivity superlattices. The high Seebeck coefficient, the order of magnitude improvement in cross-plane conductivity, and the low thermal conductivity in LSMO/LMO superlattices resulted in a two order of magnitude increase in cross-plane power factor and thermoelectric figure of merit (ZT), compared to the properties of superlattices with higher resistivity that were reported previously. The temperature dependence of the cross-plane power factor in low resistance superlattices suggests a direction for further investigations of the potential LSMO/LMO oxide superlattices for thermoelectric devices. [ABSTRACT FROM AUTHOR]

One-dimensional nanobelts of tin (IV) oxide are synthesized by using a newly introduced catalyst-assisted pulsed laser deposition method along two growth directions of [010] and [101]. An ex situ mask-induced growth gradient technique is employed to investigate the growth evolution of the nanobelts on oxidized-Si, H-terminated Si, and Al2O3(0001) substrates by helium ion microscopy, which reveals four stages of growth including catalyst detachment, horizontal nanorod growth, deflection, and the final nanobelt growth. X-ray diffraction and transmission electron microscopy studies show that in spite of the deflections and changes in the growth direction, the nanobelts have, remarkably, maintained their single-crystalline structure throughout the growth by only changing their crystalline growth axis. This has enabled us to influence the preferred growth axis by establishing a crystalline relation between the nanobelts and an appropriate substrate that pins the nanobelts in the initial growth stage. This growth control provides an important means to selectively promote growth of the predominant side planes of the nanobelts, which can then be separated for appropriate applications based on the different growth kinetics of [010] and [101] growth direction. [ABSTRACT FROM AUTHOR]

CdTe:Cu films were grown by pulsed laser deposition on Corning glass slides at a substrate temperature of 300 °C. The thin films were grown using CdTe and Cu2Te powders, varying the Cu2Te concentration from 3 to 10 wt. %. The structural, compositional, optical, and electrical properties were analyzed as a function of the nominal copper concentration. X-ray diffraction shows that films have CdTe cubic phase. The compositional analysis indicates that CdTe:Cu films grown with lower Cu content have Te excess, on the other hand, films with higher Cu content have Te deficiencies. The electrical measurements showed that CdTe:Cu films grown with low Cu content present lowest resistivity. [ABSTRACT FROM AUTHOR]

Artificial long-period superlattices of antiferromagnetic LaMnO3 and SrMnO3 ([(LaMnO3)n/(SrMnO3)n]m with n ≥ 3) were deposited on SrTiO3 (001) substrates by pulsed laser depositon monitored in situ by reflective high-energy electron diffraction. X-ray diffraction and atomic force microscopy studies reveal the sharp interfaces and smooth surface in the superlattices. Magnetic and transport characteristics are observed to depend strongly on the period of the superlattice. An interfacial ferromagnetic phase is found to coexist with the two antiferromagnetic components. The observed ferromagnetic magnetization is ascribed to Mn3+-O-Mn4+ double exchange across the LaMnO3/SrMnO3 interface. The spin-glass-like behaviors, the large magnetoresistance, and the evolution of the transport mechanism with increasing period in the superlattices are discussed in terms of spin frustration due to the competition between the ferromagnetic and antiferromagnetic interactions. [ABSTRACT FROM AUTHOR]

Polycrystalline NiFe2O4 (NFO) thin films are grown on (111) platinized Si substrates via chemical solution processing. θ-2θ x-ray diffraction, x-ray pole figures and electron diffraction indicate that the NFO has a high degree of <111> uniaxial texture normal to the film plane. The texturing is initiated by nucleation of (111) planes at the Pt interface and is enhanced with decreasing film thickness. As the NFO magnetic easy-axis is <111>, the out-of-plane magnetization exhibits improved Mr/Ms and coercivity with respect to randomly oriented films on silicon substrates. The out-of-plane Mr/Ms ratio for (111) textured NFO thin film is improved from 30% in 150 nm-thick films to above 70% in 50 nm-thick films. The improved out-of-plane magnetic anisotropy is comparable to epitaxial NFO films of comparable thickness deposited by pulsed laser deposition and sputtering. [ABSTRACT FROM AUTHOR]

This work is aimed at studying asymmetric BaTiO 3 1 − x Λ / BaZrO 3 x Λ ((BT) 1 − x Λ /(BZ) x Λ ) superlattices, grown by pulsed laser deposition onto (001) MgO substrates. The thicknesses of BT (ferroelectric) and BZ (paraelectric) layers were varied so that х ranged from 0 to 1 at a modulation period Λ of about 80 Å. The films were 400 nm thick. The out-of-plane lattice parameters of constituents were assessed using X-ray diffraction. The lattice dynamic peculiarities of superlattices were probed via Raman spectroscopy; special attention is paid to the analysis of E(1TO) and A1(2TO) ferroelectric soft modes. A comparative analysis of data acquired via both experimental techniques reveals the enhancement of stress between BT and BZ layers with a decrease in symmetry from the tetragonal to a monoclinic phase due to strains induced by the lattice parameter mismatch between the constituents. [ABSTRACT FROM AUTHOR]

The current study was achieved on the effects of laser energy and annealing temperature on x-ray structural and optical properties, such as the UV-Visible spectra of cadmium sulfide (CdS). The films were prepared using pules laser deposition technique (PLD) under vacuum at a pressure of 2.5×10-2 mbar with different laser energies (500-800 mJ) and annealing at a temperature of 473K. X-ray diffraction patterns and intensity curves for the CdS showed that the formation of CdS multi-crystallization films at all laser energies. The optical properties of the films were studied and the variables affecting them were investigated in relation to laser energy and changes in temperature. [ABSTRACT FROM AUTHOR]

In-situ X-ray diffraction experiments were performed during Laser Metal Deposition of steel X40CrMoV5-1 at the Deutsches Elektronen-Synchrotron (DESY). The measurements were performed with monochromatic high-energy X-ray radiation in transmission, while full diffraction rings were recorded at 10 Hz. The first generated layer is remelted until deposition of the third layer on top, while partial re-austenitizing of the first layer occurs until deposition of the 7th layer. Self-tempering effects were analyzed based on martensite tetragonality. Strong decrease of carbon content in solution in martensite occurs during the deposition of the first five layers, resulting in low local hardness. Image, graphical abstract [ABSTRACT FROM AUTHOR]