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This effort aimed to investigate the differences between raw materials and thin films to enhance the film performance and get encouraging results. Barium strontium titanate (BST) is a solid solution consisting of titanate barium (BT) and titanate strontium (ST). BST powder was synthesized using the sol–gel process, and BST film was deposited using pulsed laser deposition (PLD). Barium, strontium acetate, and Ti-isopropoxide were utilized as raw material sources. XRD was used to characterize the BST perovskite crystal structure. The SEM and LCR meters revealed morphology surface and dielectric properties. XRD pattern shows a cubic structure phase. The particle size of the bulk exhibited 122.88 nm while the film particle size was 84 nm. The dielectric constant of the bulk shape exhibited was greater than the form of the films, which was attributed to different thicknesses, densities, defects, and porosity. [ABSTRACT FROM AUTHOR]

In this work, we have synthesized ZnO:Al thin films by pulsed laser deposition technique and investigated their microstructural and optical properties. The XRD study confirmed a polycrystalline structure of wurtzite ZnO in all films. Further, Al doping has improved the crystallinity and decreased the crystal size and volume of the unit cell. The surface morphology was homogeneous with nanoscopic crystals clustered to form granular nanoparticles. The optical properties significantly improved by increasing the Al doping concentration. The produced thin films are excellent candidates for use as an anti-reflection layer in solar cells due to their outstanding properties. [ABSTRACT FROM AUTHOR]

Modeling the impact of a laser heat source on Ti6Al4V deposition is crucial for optimizing additive manufacturing, particularly in multi-layer contexts. This modeling provides insights into the material’s behavior during the Ti6Al4V manufacturing process. In this study, simulations using MSC Marc were conducted to model the impact of a laser heat source on the deposition of the multi-layer Ti–6Al–4V (abbreviated as Ti6Al4V) using the Ti–6Al–4V metal powder, followed by SE-FIT simulation to characterize their deposition morphology. MSC Marc was utilized to simulate the impact of a laser heat source on the Ti6Al4V, with a focus on identifying the melting area. Thermal conductivity was represented in the form of a chart as a function of temperature. Next, the morphology after deposition was defined using SE-FIT based on volume and boundaries. In the MSC Marc numerical model, a combined heat transfer coefficient of radiation and convection was applied to the convective coefficient. In the section depicting the multi-layered deposition morphology, a laser with 750W power was utilized at a speed of 3.3mm/s. After simulation, the resulting layer height and appearance were compared with the literature for a 25-layer composite. The practical implications of this research extend to the broader field of laser-induced heat deposition on Ti6Al4V deposition, which has applications beyond titanium alloys. The findings may contribute to advancements in the design and manufacturing of various metal components, impacting industries such as automotive, electronics and energy. [ABSTRACT FROM AUTHOR]

Several researchers have recently expressed interest in additively manufactured electrodes for machining and surface modification applications. The additively manufactured AlSi10Mg tool electrode is one of the promising candidate materials for non-conventional processes. This research investigates the process parameters of laser powder bed fusion (L-PBF) processed AlSi10Mg tool electrodes for the electro-spark deposition process (ESD). The selected deposition parameters, namely, peak current (Pc), pulse-on time (Pon) and deposition time (DT) with various levels and experimentation, are based on the box-behnken design (BBD) of the response surface methodology. The deposition was carried out to analyze the output responses of material deposition rate (MDR), additive tool wear rate (ATWR) and surface roughness (SR). The multi-objective optimization was performed to minimize the ATWR and SR and maximize the MDR. The optimized ESD parameters of Pc = 6 A, Pon = 20 μ s, and DT = 5 min were found with predicted responses of MDR = 0.019 mg/min, ATWR = 0.095 mg/min and SR = 3.86 μ m. The deposited surface witnessed the formation of debris, microcracks, and a solidified surface with a dark region and accumulated worn debris that has an elongated and flat shape. The workpiece substrate was exposed to a significant amount of additive tool electrode material (Si, Al, O, Mg, S), and different intermetallic ( Al 2 6 Si) 0.148, Al2O3, and Al2S3 formations have been recognized. This finding corroborates the efficient usage of L-PBF AlSi10Mg electrodes for ESD processes. [ABSTRACT FROM AUTHOR]

Zinc selenide (ZnSe) nanostructure's optical and structural characteristics were investigated in this study. Pulse laser deposition of thin films on glass substrates was achieved using an Nd:YAG laser (wavelength 1064 nm) at different laser powers (100, 200, 300, 400 and 500 mJ) with fixed pulses 100 pulses, repetition rate 6 Hz and distance 10 cm between laser and the substrate with a thickness of films 200 nm. An atomic force microscope (AFM) and X-ray diffraction method were used to research the impact of altering the laser intensity on the structural characteristics. A branched (100) polycrystalline type and a plane (111) and branched (100) polycrystalline type are prevalent (002). In addition, AFM measurements further revealed that the smallest granular size achieved at high laser power was 48.40 nm at 100 mJ. The findings showed that it is possible to construct nanostructures with medium grain sizes of alumina (72.99 nm). The study of the relationship between laser energy and nanostructure optical characteristics was explored and it was discovered that the transitions had a specific range of 2.83–3.10 eV. [ABSTRACT FROM AUTHOR]

The mixed-valence perovskite manganites attracted much attention because of their interesting electro-magnetic properties, and strain modulation on magnetic properties of perovskite manganites is worth exploring. In this paper, [La 0. 8 Ca 0. 2 MnO3/La 0. 5 Ca 0. 5 MnO3] 2 0 superlattice films with different La 0. 8 Ca 0. 2 MnO3 layer thicknesses are prepared by pulsed laser deposition (PLD). The crystal structures (lattice constants) of samples are measured by X-ray diffraction (XRD). The strain of the films is determined according to their crystal structures. The magnetic hysteresis loops (M-H loops) and magnetization versus temperature (M-T) curves of these superlattice films are measured by the physical property measurement system (PPMS). From the M-H loops, the coercive field (H C) of the samples can be measured. From the M-T curves, the Curie temperature (T C) of the samples can be obtained. All samples show a ferromagnetic to paramagnetic transition at TC, and the [La 0. 8 Ca 0. 2 MnO3/La 0. 5 Ca 0. 5 MnO3] 2 0 sample with the La 0. 8 Ca 0. 2 MnO3 layer thicknesses of 72 Å has an antiferromagnetic Néel transition at TN. According to the strain state and magnetic phases, the magnetic properties are comprehensively analyzed. It is found that with the increase of ferromagnetic La 0. 8 Ca 0. 2 MnO3 layer thickness, the ferromagnetic phase is increased, and the double exchange effect can also be enhanced, resulting in the increase of TC. When the thickness of La 0. 8 Ca 0. 2 MnO3 reaches 96 Å, the uneven strain distribution in the superlattice can induce the reduction of ferromagnetic phase compared with antiferromagnetic phase (even antiferromagnetic phase starts to appear), and the double exchange effect can be weakened, and finally leading to the decrease of TC. In addition, with increasing the La 0. 8 Ca 0. 2 MnO3 layer thickness, HC gradually decreases. The change of HC is related to strain states and magnetic phase interactions in the samples. The analysis of the strain and magnetism can contribute to the understanding of perovskite manganite superlattice films. [ABSTRACT FROM AUTHOR]

Iron–phthalocyanine (FePc) organic photoconductive detector was fabricated using pulsed laser deposition (PLD) technique to work in ultraviolet (UV) and visible regions. The organic semiconductor material (iron phthalocyanine) was deposited on n-type silicon wafer (Si) substrates at different thicknesses (100, 200 and 300) nm. FePc organic photoconductive detector has been improved by two methods: the first is to manufacture the detector on PSi substrates, and the second is by coating the detector with polyamide–nylon polymer to enhance the photoconductivity of the FePc detector. The current–voltage (I–V) characteristics, responsivity, photocurrent gain, response time and the quantum efficiency of the fabricated photoconductive detector were measured. The performance of the fabricated detector was taken under dark and illumination using two types of light sources: UV LED with wavelength (365 nm), power of (10 W) and Tungsten lamp with wavelength range between (500–800) nm and the optical power of (250 W). The photoresponse enhancement was improved by coating the FePc films with 200 nm of polyamide nylon polymer. This type of coating, which can be considered as a surface treatment, highly increased the photoresponse of the fabricated FePc UV detector. The results show that the responsivity increased four orders of magnitudes more than the responsivity of the uncoated FePc film. The effects of the coated polymers on the responsivity and the response time of the detector were investigated. [ABSTRACT FROM AUTHOR]

Pr 0. 7 Sr 0. 3 MnO3 thin films were grown epitaxially on SrTiO3 and LaAlO3 substrates by pulse laser deposition. X-ray diffraction spectra obtained on these films revealed good crystallinity and epitaxy. It was found that the oxygen deficiency and in-plane strain may affect the transport behavior and phase transition near Curie temperature in these Pr 0. 7 Sr 0. 3 MnO3 films. Also, the resistance and metal-insulator phase transition could be modulated significantly by the applied electric currents. The reduction ratio of the peak resistance reached −38% for a bias current I = 5 0 0 μ A, demonstrating a remarkable electroresistance effect. The results are interpreted based on the spatial inhomogeneity related to the coexisted multi-phases with different electronic and magnetic properties. [ABSTRACT FROM AUTHOR]

A study using a pulsed laser deposition (PLD) technique was accomplished by growing NiTi nanoparticles on glass and stainless steel 316L substrates. The effects of laser energy state of deposition on the granule size of the NiTi nanoparticle and the structural properties of its thin film were discussed. X-ray diffraction analyses revealed that the films prepared at 65 W, 75 W, 85 W, 100 W exhibited amorphous structures. AFM results confirmed that the thin films consist of evenly distributed spherical particles. The results also showed an exponential increase in those particles' sizes. [ABSTRACT FROM AUTHOR]

The present work deals with the fabrication of forsterite–hydroxyapatite (FS–HA) hybrid coatings on stainless-steel 316L using the pulsed laser deposition (PLD) technique. The stainless steel (SS 316L) as a metallic implant is widely used in hard tissue applications. The XRD studies have confirmed the crystalline behavior of synthesized FS powder with an average crystallite size of 54 nm. The synthesized FS powder was mixed in different compositions (10, 20, 30 wt.%) into HA for preparing PLD targets (pellets). The XRD of the prepared pellets by UTM has confirmed both phases of FS and HA. The Scanning Electron Microscopy (SEM) of the coated samples depicted the successful deposition of composite powders on the substrates (SS 316 L). The Ellipsometer was used to investigate the thickness of different substrates and it was found as 243, 251, 255, and 257 nm for CP1, CP2, CP3, and CP4, respectively. The bioactivity of the coated substrates with different compositions (pure HA, 10%, 20%, 30%, and pure FS) was investigated by immersing the samples in simulated body fluid (SBF) for 14 days. The same samples were then characterized by SEM which confirms the apatite layer formation that reflects the bioactivity. The addition of FS powder into HA will stimulate the apatite formation which enhances the bioactivity. The Raman Spectroscopy of coated samples reveals the successful deposition of different compositions of FS–HA nanocomposite. The peaks of Raman spectroscopy were corresponding to the XRD results of the pellets (different compositions of FS–HA). The antimicrobial activity of different compositions of FS–HA against Escherichia coli (E. coli) bacteria also showed a significant zone of inhibition. The bioactivity and antimicrobial behavior of FS–HA along with successful deposition by PLD have shown better potential applications for biomedical implant coating. [ABSTRACT FROM AUTHOR]

In this work, a pulsed laser deposition (PLD) technique with an Nd:YAG laser source was used to produce pure Hydroxyapatite (HA) and Cu-substituted HA (Cu-HA) coatings on stainless steel substrates in vacuum at room temperature. It is observed that the combined effects of percentages of Cu dopants and laser energy as well as annealing temperature significantly modify the crystallinity of the films. The morphology and structural properties of the deposited HA films were analyzed by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and Raman spectroscopy. FESEM images displayed various shapes of nanoparticles with high-surface density throughout the area of the substrate and with typical sizes around 26–208 nm. XRD analysis confirmed that post-deposition annealing is essential to achieve the desired crystallinity and uniformity of coatings. The Raman spectrum of HA has peaks at 958.22, 437.48, and 587.05 cm − 1 attributed to the ν 1 PO 4 3 − , ν 2 PO 4 3 − , and ν 3 PO 4 3 − , respectively. The synthesized HA and Cu-HA crystalline films are nanostructures with dense and compact microstructures. Finally, irregular surface and crystalline structure of fabricated films lead to the extension of the surface and enhance the cell's proliferation in medical uses and biomedical applications. [ABSTRACT FROM AUTHOR]

Crystalline silicon substrate visible light reflectivity is finely modified by a discrete growth of carbon nanofilm (CNF) on it by nanosecond pulsed laser deposition (PLD) technique. It is established that 71 nm thick CNF effectively reduces the high reflection of the substrate on average to 5% in the visible light wave range. The exact values of the thickness and refractive index of the carbon nanofilm are also determined via an analysis of reflection spectra. [ABSTRACT FROM AUTHOR]

In the quantum system of nanolayer (NL) on silicon, the bandgap energy obviously increases with the decrease of NL thickness, where the quantum confinement (QC) effect plays the main role as the thickness of Si NL changes along with (100), (110) and (111) directions, respectively. And the simulation result demonstrated that the direct bandgap can be obtained as the NL with (001) direction is thinner than 10 nm on Si surface. However, it is discovered in the simulated calculation that the QC effect disappears as the NL thickness arrives at the size of the monoatomic layer, in which its bandgap sharply decreases, where the abrupt change effect in bandgap energy occurs near-ideal 2D-layer. In the experiment, we fabricated the Si NL structure by using electron beam irradiation and laser deposition methods, in which a novel way was used to control the NL thickness by modulating irradiation time of the electron beam. The new effect should have a good application on a photonic-electronic chip of silicon. It is discovered in the simulated calculation that the quantum confinement effect disappears as the NL thickness arrives at size of monoatomic layer, in which its bandgap sharply deceases, where the abrupt change effect in bandgap energy occurs near ideal 2D-layer. [ABSTRACT FROM AUTHOR]

We have presented the structural, surface morphology, magnetic and resistivity data for perovskite LaMnO3 epitaxial thin films which are fabricated on well-oriented (001) LaAlO3 substrates by pulsed laser deposition technique. X-ray diffraction 𝜃 – 2 𝜃 linear scans and reciprocal space mapping measurement confirm that the out-of-plane and in-plane epitaxial relationship are LMO(001)/LAO(001) and LMO(110)/LAO(110), respectively. Surface roughness determined by atomic force microscopy was no more than 0.3 nm. In the whole studied temperature range, all films only show a paramagnetic behavior instead of any magnetic phase transitions. Correspondingly, the electron transport behaviors always exhibit an insulting state as the temperature changes from high to low. However, we find that none of theoretical models can individually be used to understand their conductive mechanisms. Further studies indicated that charge carries of high and low temperature region obey adiabatic and nonadiabatic small polaronic hopping mechanisms, respectively. This finding offers new ways of exploiting the abnormal ferromagnetism in LaMnO3 multilayer thin films. [ABSTRACT FROM AUTHOR]

Hydrophobic antireflective coating is fabricated by physical vapor deposition. The optical, contact angle and laser damage resistance properties are investigated, respectively. The transmittance of the antireflective coating with hydrophobic layer is 99.58% at 1064 nm with normal incidence. The contact angle with water is 115.6 ∘ . The laser damage threshold of the zero probability is 22 J/cm2 at 1064 nm with the 12 ns pulse width. This new hydrophobic antireflective coating can be applied in the areas of astronomical optics, laser medical equipment and solar energy, etc. [ABSTRACT FROM AUTHOR]

Single-perovskite lead-free BaTiO3 ferroelectric films were synthesized on Nb:SrTiO3 substrates by pulsed laser deposition. The microstructure, ferroelectric, electric-field breakdown strength, and energy-storage properties of films were investigated. The remnant polarization (P r) reached the higher values of 34.79 μ C/cm2. The recoverable energy-storage density (U Re ) is 12.30 J/cm3. The results also reveal that rapid thermal processing (RTP) enhances the ferroelectric and energy storage properties of the film by comparison with unannealed, and ferroelectric and energy storage properties exhibit a strong voltage dependence. [ABSTRACT FROM AUTHOR]

NiTi Shape Memory Alloy (SMA) is now widely used in important applications due to its shape memory effect (SME) and biocompatibility. However, there is still a challenge to control the sizes and shapes of these nanoparticles. Here, we report on the use of pulsed laser deposition technique for the cultivation of NiTi nanoparticles on glass substrates. It discussed the implications of the case of the influence of depositing laser energy on the size of a grain of NiTi nanoparticle. The nominated effect on the optical properties of its thin-film was also discussed. X-ray diffraction (XRD) analysis revealed that the films prepared at 800 mJ, 900 mJ and 1000 mJ were amorphous structures. The Atomic Force Microscopy (AFM) results confirmed that the thin films are made up of spherical particles that are evenly distributed (in terms of size). A blueshift in the bandgap was observed in the UV–Visible absorption spectra with increase in the depositing laser energy due to the quantum confinement effect of nanoparticle formation. [ABSTRACT FROM AUTHOR]

In this study, indium tin oxide (ITO) was deposited onto sapphire and low resistive p-Si substrates using pulsed laser deposition (PLD) technique. The optical energy gap of ITO deposited on the sapphire substrate was 3.7 eV at room temperature. Photoluminescence (PL) of ITO shows an emission of broad peak at 524 nm. Photovoltaic (PV) characteristics of the n-ITO/p-Si heterojunction are examined and showed conversion efficiency (η) of 1.8%. The open circuit voltage (V OC ) for this cell was 0.49 V while the short circuit current density (J SC ) was 17.4 mA/cm2. The fill factor of this cell was 22%. The ideality factor of ITO/Si heterojunction is about 3.1. The barrier height Φ B of the heterojunction was determined from I–V characteristics and was 0.83 eV. The responsivity of the heterojunction was measured and the maximum value of responsivity was 0.5 A/W without bias voltage. The minority carrier lifetime of the solar was measured using open circuit voltage decay (OCVD) method and found to be 227 μ s. [ABSTRACT FROM AUTHOR]

The dynamic mechanism of the velocity splitting during the nucleation and growth of silicon nanoparticles produced by pulsed laser deposition is investigated using the Monte Carlo simulation method. Compared with the previous works, the earlier onset and end of the splitting phenomenon are found due to the nucleation and growth of Si nanoparticles in this paper. More importantly, our simulated results are more precisely consistent with the previous experimental data. The extrusion pressure and velocity elasticity of the "particle cluster" are proposed, it is the imbalance between them that induces the velocity splitting. [ABSTRACT FROM AUTHOR]

The study of complex oxides and oxide heterostructures has dominated the field of experimental and theoretical condensed matter research for the better part of the last few decades. Powerful experimental techniques such as molecular beam epitaxy and pulsed laser deposition have made fabrication of oxide heterostructures with atomically sharp interfaces possible, whereas more and more sophisticated handling of exchange and correlations within first principles methods including density functional theory (DFT) supplemented with Hubbard U corrections and hybrid functionals, and beyond DFT techniques such as dynamical mean field theory (DMFT) have made understanding of such correlated oxides and oxide interfaces easier. The emergence of the high-mobility two-dimensional electron gas with fascinating properties such as giant photoconductance, large negative magnetoresistance, superconductivity, ferromagnetism, and the mysterious coexistence of the latter two have indeed caught the attention of condensed matter community at large. Similarly, strain tuning of oxides have generated considerable interest particularly after the recent discovery of piezoelectric methods of strain generation. Theoretical understanding and prediction of the possible exotic phases emerging in such complex oxides both under strain and in heterostructures will eventually lead to better design of device applications in this new emerging field of oxide electronics, along with possible discovery of exotic physics in condensed matter systems, which may be of wider significance! In this review, we briefly look at theoretical studies of novel phenomena in oxides under strain and oxide heterostructure, and try to understand the role of exchange and particularly correlation in giving rise to such exotic electronic states. This review though primarily focuses on the theoretical aspects on understanding the different mechanism of the phenomena of emergence of exotic phases, does provide a unique overview of the experimental literature as well, accompanied by the theoretical understanding such that relevant device applications can be envisaged. [ABSTRACT FROM AUTHOR]

Amorphous and crystalline Zn 1 − x CoxS (x = 0. 1 , 0.3, 0.5) thin films were grown on sapphire (Al2O3) substrates by pulsed laser deposition at substrate temperature of 25∘C and 800∘C, respectively. The X-ray diffraction results show that the crystalline film has a cubic zinc blende structure and the crystalline quality decreased with increasing Co-doping concentration. The X-ray diffraction and X-ray photoelectron spectroscopy spectra reveal that the samples reached an overdoping state at Co-doping concentration of x = 0. 5. The absorbance of films increases and the absorption edge shifts to longer wave length direction with increasing Co-doping concentration. The redshift of the band gap energy depends on the Co composition associating with the Urbach energy. Furthermore, the refractive index and dielectric constant increase with increasing Co-doping concentration. The dispersion parameters, such as dispersion energy ( E d ), oscillator energy ( E o ), static refractive index ( n 0 ), static dielectric constant ( ϵ 0 ), interband transition strength moments ( M − 1 and M − 3 ), oscillator strength S o and oscillator wavelength λ o , have been analyzed by Wemple–DiDomenico single oscillator model. All these parameters were found to be dependent upon the Co-doping concentration in the Zn 1 − x CoxS thin films. [ABSTRACT FROM AUTHOR]

The dynamic mechanical properties of Ti-6Al-4V alloy prepared by laser direct deposition (LDD) at different strain rates are of great significance for the application of LDD technology in the manufacture and repair of aero-engine parts. The quasi-static tensile test and dynamic compression test of Ti-6Al-4V alloy prepared by LDD (LDD-Ti-6Al-4V) were carried out under the quasi-static and high strain rate using INSTRON-5982 tensile test equipment and Split Hopkinson pressure bar (SHPB) equipment. The true stress–strain curve is obtained, which indicates that the LDD-Ti-6Al-4V has a strain rate strengthening effect. Moreover, the Johnson–Cook (J–C) constitutive model of LDD-Ti-6Al-4V was fitted based on experimental data, and the experimental process of SHPB was numerically simulated. The simulation results are basically the same as the experimental results, which proves the correctness of the J–C constitutive model of LDD-Ti-6Al-4V. [ABSTRACT FROM AUTHOR]

In this work, TiAlV thin films have been prepared on two different types of substrates: silicon and stainless steel (SS304) by two deposition methods: Pulsed Laser Deposition (PLD) and DC magnetron sputtering. Different techniques have been employed in order to characterize film properties such as: Scanning Electron Microscopy (SEM) equipped with Energy Dispersive X-ray (EDX), X-ray diffraction (XRD), microhardness and corrosion test. EDX analysis showed that the deposited films are slightly different from that of the target material Ti6Al4V alloy. The measured microhardness values are about 11.7 GPa and 4.7 GPa for films prepared by PLD and DC magnetron sputtering, respectively. Corrosion test indicated that the corrosion resistance of the two TiAlV films deposited on SS304 substrates in (0.9% NaCl) physiological normal saline medium was significantly improved compared with the SS304 substrates. These attractive results could permit applications of our films in the medical implants fabrication. [ABSTRACT FROM AUTHOR]

We have grown, by Pulsed Laser Deposition (PLD), a large number of YBa2Cu3O7 films with artificial pinning centers, with various impurities, various architectures and thickness, and various techniques of nano-scale pinning engineering: substrate decoration, BaZrO3 (BZO) nano-inclusions, and (quasi) multilayer architecture. Here we will present the results regarding vortex matter, dynamics, and pinning, in some of our best samples. Magnetic relaxation studies with magnetic field perpendicular to the film show that in both cases the splayed defects and/or nanoscale inclusions help reduce the dissipation in certain field-temperature range, by inhibiting the detrimental double vortex-kink formation. The response of the vortex system to AC excitation is rather complex but extremely useful for the characterization of the vortex dynamics. We have measured AC susceptibility in various DC fields, with various AC fields and frequencies and found that the effective vortex activation energy U eff has a logarithmic dependence on the AC-field-induced current density J. Synergetic pinning centers assured a low anisotropy of the critical current for various field orientations, a property desired in coil/solenoid applications. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V alloy is restricted in industrial application as a result of its relatively low hardness and poor tribological properties. However, the limitations associated with Ti-6Al-4V in severe tribological conditions can be improved via laser cladding technique. In this study, the influence of rare earth oxide (CeO 2) addition on microstructure, hardness and tribological behavior of laser-clad titanium–cobalt-based coatings on Ti6Al4V alloy was investigated. The optimized parameters used for laser depositions are laser power 900 W; beam spot size 3 mm; powder feed rate 1.0 g/min; gas flow rate 1.2 L/min while laser scan speed was varied at 0.6 m/min and 1.2 m/min. Thereafter, the coating morphology as well as wear mechanism of the coatings of CeO2 particles (5–10 wt.%) dispersed in TiCo matrix were investigated via scanning electron microscope (SEM) equipped with energy dispersed spectrometry (EDS), whereas the intermetallic phases present in the coatings were observed using Philips PW1713 X-ray diffractometer (XRD). Furthermore, the micro-hardness values of the coatings were recorded while wear test was carried out using a reciprocating set up (UMT-2 — CETR tribometer). Results revealed that the incorporation of CeO2 particles into the melt pool influenced the morphology of the coatings, thus resulting in finer cellular dendrites, homogenous and strong metallurgical bonding between the laser cladded coating and the substrate. The phases revealed various fractions of interdendritic compounds (CeCo2, Ni3Ti, Co2Ti, CoTi, Al2O3, TiO, AlTi3, and Ce2O 3) dispersed within the coating matrix, thus resulting in 2.68 times improvement on the surface hardness and 47.4% reduction in friction coefficient in comparison with Ti-6Al-4V alloy. [ABSTRACT FROM AUTHOR]

ZnO/Zn 1 − x Mg x O asymmetric quantum barriers on JGS1 quartz glass and Al 2 O 3 substrates were prepared by a pulsed laser deposition (PLD) technique. Microstructure characterization confirmed the designed structure. Because of the design of ZnO/Zn 1 − x Mg x O asymmetric quantum barrier, representative exciton peaks were observed in the optical absorption spectrum at room-temperature. This confirmed that the designed ZnO/Zn 1 − x Mg x O asymmetric quantum barrier structure realized the quantum-binding effect at room-temperature. Moreover, when x = 0. 1 5 , the asymmetric quantum barrier structure had optimum performance compared with other x values. [ABSTRACT FROM AUTHOR]

Temperature-dependent (5–200 K) electrical resistivity and magnetoresistance (MR) measurements were carried out on Zn 1 − x V x O (x = 0.5–4 at.%) thin films grown by pulsed laser deposition (PLD). The free electron concentration in the films was found to be in the range of ∼ (1.7–4.7) × 1 0 2 0 cm − 3 which is much higher compared to the Mott critical density required for the onset of insulator-to-metal transition in ZnO. All the films exhibited small negative MR in the entire temperature and magnetic field range indicating weak-localization as the dominant effect. However, some unusual MR behavior was observed at 5 K for the film with highest static-disorder parameter. Such characteristics have been well-explained by considering the interplay of negative MR (arising due weak-localization and spin-disorder scattering) and positive MR (caused by s–d exchange interaction induced spin-splitting of the conduction band). [ABSTRACT FROM AUTHOR]

Zn 0. 9 Se:Co 0. 1 thin films were deposited on sapphire (Al2O3) substrates in argon atmosphere at various gas pressures by pulsed laser deposition. Influence of argon pressure on the thickness, surface morphology, crystal structure and optical properties of the thin films were investigated by various diagnosis tools. It was found that these physical properties were correlated to the argon pressure and appeared like a mutation between the pressure of 2 Pa and 4 Pa. As the deposition pressure changed from 2 Pa to 4 Pa, the collision probability between ablated species and argon molecule was increased, which resulted in the transformation of the deposition type from sputter effect to adsorption effect and the mutation of film thickness and structure. These in turn influence the transmission range and band gap of the films. All of the results suggest that the ambient pressure is a very important factor to the deposition of Zn 0. 9 Se:Co 0. 1 films by PLD. [ABSTRACT FROM AUTHOR]

Multiferroic NiFe 2 O 4 / 0. 8 BaTiO 3 – 0. 2 Na 0. 5 Bi 0. 5 TiO 3 bilayer thin film epitaxially grown on (001)- SrRuO 3 / SrTiO 3 substrate was prepared by pulsed laser deposition. Excellent ferroelectric, magnetoelectric properties and a higher Curie temperature were observed in the NiFe 2 O 4 / 0. 8 BaTiO 3 – 0. 2 Na 0. 5 Bi 0. 5 TiO 3 composite thin film compared with the NiFe 2 O 4 / BaTiO 3 composite thin film. In particular, the remnant and saturated polarizations of NiFe 2 O 4 / 0. 8 BaTiO 3 – 0. 2 Na 0. 5 Bi 0. 5 TiO 3 are 3 5. 2 μ C/cm 2 and 9 6. 1 μ C/cm 2 , respectively, and the maximum magnetoelectric coefficient can reach up to 9 6 mV ⋅ cm − 1 ⋅ Oe − 1 , which are larger than those of the NiFe 2 O 4 / BaTiO 3 composite thin film (18.8, 4 4. 5 μ C/cm 2 , and 6 0 mV ⋅ cm − 1 ⋅ Oe − 1 ). [ABSTRACT FROM AUTHOR]

A Ni–Fe–B–Si–Nb amorphous alloy was deposited on a steel substrate surface via a laser cladding process, and a laser cladding plus laser remelting process. The wear behavior of the laser processed samples and the bulk metallic glass (BMG) sample with the same nominal composition were tested using a pin-on-disc type testing machine. The nano-mechanical properties of the samples were measured with a nano-characterization system. The friction wear tests showed that deep grooves and wear debris were formed on the worn surface of the laser cladded coating, while only shallow grooves for the laser remelted coatings. The friction coefficients of laser remelted coatings and BMG were lower than the laser cladded coating. The wear mass losses of the laser remelted coating were less than the BMG when the laser remelting scanning speed was higher than 6 mm/min. The nano-hardness and elastic modulus of the remelted coating is higher than that of the laser cladded coating. Also, they increase with the increasing laser scanning speed with 1227.9 HV and 277.4 GPa when the remelting scanning speed is 8 m/min. Based on the nano-indentation and friction wear tests results, it was found that the friction wear properties of the laser cladded coating, laser remelted coatings and BMG related well to the ratio of H3/E2. A higher value of H3/E2 can lead to a better wear resistance property. [ABSTRACT FROM AUTHOR]

Titanium (Ti) thin films with (002) or (100) texture are favored for many applications. In this paper, Ti thin films were prepared by high-power pulsed magnetron sputtering, and the texture of Ti thin films was successfully tailored by adjusting the pulse width, substrate bias and magnetic field strength. It is found that the peak power and average power of the Ti target are increased by increasing sputtering pulse width and decreasing magnetic field strength, which raise the Ti plasma flux and ion/atom ratio of Ti ions in front of the substrate simultaneously. Ti thin films with a highly (002) out-of-plane texture can be obtained with higher pulse width and lower magnetic field strength. The Ti thin films with highly (100) out-of-plane texture can be achieved with shorter pulse width, lower magnetic field strength and substrate bias. [ABSTRACT FROM AUTHOR]

The amorphous oxygen-doped diamond-like carbon films were prepared by pulsed laser deposition. Compared with the pure diamond-like carbon film, there were much less graphite clusters on the surfaces of the oxygen-doped diamond-like carbon films, and the average transmission of the oxygen-doped diamond-like carbon films in the medium infrared band increased. However, some new absorption peaks in the infrared spectra of the oxygen-doped diamond-like carbon film were generated. Rapid annealing was experimented to remove the absorption peaks. XPS analysis showed that the fractions of the C–O and C=O bonds that generated the new absorption peaks were reduced more than the fractions of s p 3 bonds by rapid annealing at 400 ∘ C, and the absorption peaks in the medium infrared spectra decreased. It indicated that rapid annealing at right temperature during the right time could reduce greatly the absorption in the medium infrared band of oxygen-doped diamond-like carbon films. [ABSTRACT FROM AUTHOR]

In the scaling down of electronic devices, functional oxides with strongly correlated electron system provide advantages to conventional semiconductors. We report the fabrication of the electric double layer transistor (EDLT) with the (La,Pr,Ca)MnO3 (LPCMO) epitaxial nanowall wire (NW) channel whose width was less than 100 nm. The width controlled LPCMO NWs were fabricated using an original nanofabrication technique: 3D nanotemplate pulsed laser deposition. The LPCMO NW EDLT was produced by employing 80 nm width NWs as channel. The produced LPCMO NW EDLT showed low leakage current. The metal-insulator transition property was successfully modulated by gating effect on the LPCMO NW EDLT. [ABSTRACT FROM AUTHOR]

The Cd x Zn 1 − x O thin films have been deposited on glass and Si substrates at room-temperature with different Cd contents (x = 0, 2%, 4% and 6 wt.%) by pulsed laser deposition (PLD) technique. X-ray diffraction (XRD) analyses evidenced that the films possess polycrystalline and a hexagonal ZnO crystal structure for x = 0, 2% and 4% with a preferred orientation in the a-axis (101) direction, while films with a mixed hexagonal and cubic structure was revealed for x = 6 wt.%. Electrical measurement presented that the resistivity decreased with increased temperature and concentration of Cd. The deliberated activation energy was reduced was from 0.224 to 0.113 eV with increase doping concentration. Current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the fabricated Cd x Zn 1 − x O/p-Si heterojunction varied with the applied bias and the Cd concentration. The results of the values of built-in potential (V bi ) and the ideality factor (n) increased with raising Cd concentration. [ABSTRACT FROM AUTHOR]

The influence of oxygen atmosphere and substrate temperature on morphology and microstructure of the hydroxyapatite (HA) composite films prepared by pulsed laser deposition (PLD) was studied. According to the results of X-ray diffraction (XRD), scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR), it was found that the phase compositions and the crystallinity of HA were affected by the oxygen pressure and substrate temperature. High oxygen pressure can increase the crystallinity of HA, and make random oriented HA gradually transform into c -axis orientation, and decrease the Ca/P atomic ratio of the film. High substrate temperature can increase the crystallinity of films and the degree of c-axis orientation of HA, but increase the Ca/P atomic ratio slightly. Changes of oxygen pressure or substrate temperature have little influence on the surface morphology and thickness of film. Valuable HA composite film could be obtained at 600 ∘ C under 5 Pa O2 atmosphere. [ABSTRACT FROM AUTHOR]

Nonhydrogen germanium carbide (GexC 1 − x ) films were prepared by KrF pulsed lasers deposition (PLD), and the effects of different germanium contents on the microstructures, optical properties and adhesion properties of the GexC 1 − x films were studied. XRD measurements showed that the GexC 1 − x films with different germanium contents were of amorphous structure. XPS analysis showed that the C/Ge atomic ratios of GexC 1 − x films were close to those of corresponding targets. The intensity of Ge3 d peak in the GexC 1 − x films increased and the intensity of C1s peak decreased with the increase of the germanium content. The GexC 1 − x films' s p 3 C bond contents increased from 46.4% to 69.7%. Ellipsometry and infrared transmission spectral measurements showed that the refractive index of GexC 1 − x films increased from 2.5 to 3.5 at the wavelength of 1 μ m with the increase of germanium content. The extinction coefficient of GexC 1 − x film was of the order of 10 − 3 in the infrared band when the germanium content was less than 10 at.%. The adhesion tests showed that the adhesion performances of GexC 1 − x films were better when the germanium content increased. [ABSTRACT FROM AUTHOR]

Aluminum (0.5 at.%)-doped ZnO (AZO) thin films were deposited by pulsed laser deposition technique (PLD) in oxygen ambient of 10 − 6  Torr. The deposited thin films were characterized by x-ray diffraction (XRD), photoluminescence (PL), Raman spectroscopy and uv–visible spectroscopy (UV–vis). Next, graphene oxide (GO) was synthesized by Hummers method and was characterized by XRD, UV–vis spectroscopy, Raman spectroscopy and transmission electron microscopy (TEM). Thereafter, GO solution was drop-casted on AZO thin films. These films were then characterized by Raman Spectroscopy, UV–vis spectroscopy and PL. Attempt is being made to comprehend the modifications in properties brought about by integration. [ABSTRACT FROM AUTHOR]

The effect of substrate temperature on growth of pulsed laser deposited copper oxide thin films has been investigated by employing Nd: YAG laser (532nm, 6ns, 10Hz) irradiation at a fluence of 8.2J/cm2. XRD analysis reveals that copper oxide films deposited at room temperature are amorphous in nature, whereas films deposited at higher substrate temperatures are polycrystalline in nature. SEM and AFM analyses revealed that films deposited at substrate temperatures, ranging from room temperature to 300C are comprised of large sized clusters, islands and particulates, whereas uniform films with an appearance of granular morphology and distinct bump formation are grown at higher substrate temperatures of 400C and 500C. The optical bandgap of deposited films is evaluated by UV-VIS spectroscopy and shows a decreasing trend with increasing substrate temperature. Four point probe analysis reveals that electrical conductivity of the deposited films increases with increase in the substrate temperature, and is maximum for highest growth temperature of 500C. It is revealed that growth temperature plays a significant role for structure, texture, optical and electrical behavior of copper oxide thin films. The surface and structural properties of the deposited films are well correlated with their electrical and optical response. [ABSTRACT FROM AUTHOR]

To examine the thermodynamic phase stability of Y-Ba-Cu-O superconductors in ultrathin film form, we study the effects of high-pressure oxygen annealing and Cu enrichment on YBa2Cu3O films ranging from 8 nm to 15 nm in thickness. The films are grown epitaxially on SrTiO3 substrates by pulsed laser-ablated deposition, and post-annealed in 475 atm of oxygen at 800C while subjected to varying concentrations of excess CuO. X-ray diffraction (XRD) on the annealed films shows evidence for suppression of YBa2Cu3O and formation of Y2Ba4Cu8O. This structural transformation towards a higher-oxidation phase is expectedly correlated with film thinness and Cu enrichment. [ABSTRACT FROM AUTHOR]

LaHfMnO3 films were grown on 0.05 wt.% Nb-doped SrTiO3 substrates by pulsed laser deposition. X-ray diffraction measurements demonstrated that our samples were of good epitaxy and single-crystal. The temperature-dependent resistance has been investigated. It was observed that the as-grown film of LaHfMnO3 exhibited a typical paramagnetic-ferromagnetic transition. Heterojunctions of LaHfMnO3/0.05 wt.% Nb-doped SrTiO3 exhibited-asymmetric current-voltage characteristics and a remarkable temperature-dependent rectifying behavior in a wide temperature range (from 40 K to 300 K). And the most remarkable observation of this work is the existence of a crossover from positive to negative magnetoresistance in the LaHfMnO3/0.05 wt.% Nb-doped SrTiO3 heterojunction as the temperature decreases. A temperature-dependent magnetoresistance was studied as well. The rectifying characteristics and tunable magnetoresistance of these heterojunctions may be attributed to band structure of LaHfMnO3/0.05 wt.% Nb-doped SrTiO3 heterojunction. [ABSTRACT FROM AUTHOR]

The possibility of deposition of Fe-TiC nanocomposite on the surface of carbon steel substrate with the laser coating method had been investigated. Mechanical milling was used for the preparation of raw materials. The mixture of milled powders was used as a coating material on the substrate steel surface and a CO2 laser was used in continuous mode for coating. Microstructural studies were performed by scanning electron microscopy. Determinations of produced phases, crystallite size and mean strain have been done by X-ray diffraction. The hardness and wear resistance of coated samples were measured. The results showed that the in situ formation of Fe-TiC nanocomposite coating using laser method is possible. This coating has been successfully used to improve the hardness and wear resistance of the substrate so that the hardness increased by about six times. Coated iron and titanium carbide crystallite sizes were in the nanometer scale. [ABSTRACT FROM AUTHOR]

The electrical transport properties are the key factors to determine the performance of ZnO-based quantum effect device. ZnMgO is a typical material to regulate the band of ZnO. In order to investigate the electrical properties of the interface of ZnO/ZnMgO films, three kinds of ZnO/ZnMgO films have been fabricated with different thickness. After comparing the structural and electrical properties of the samples, we found that the independent ZnMgO hexagonal wurtzite structure (002) peak can be detected in XRD spectra. Hall-effect test data confirmed that the two-dimensional electron gas (2DEG) became lower because of the decrease of thickness of ZnMgO films, increase of impurity scattering and lattice structure distortion caused by the increase of Mg content. [ABSTRACT FROM AUTHOR]

We simulated the nucleation and growth of Si nanoparticles produced by pulse laser deposition using Monte Carlo method at the molecular (microscopic) level. In the model, the mechanism and thermodynamic conditions of nucleation and growth of Si nanoparticles were described. In a real physical scale of target-substrate configuration, the model was used to analyze the average size distribution of Si nanoparticles in argon ambient gas and the calculated results are in agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Multilayer diamond-like carbon film with germanium buffer layers, which was composed of several thick DLC layers and thin germanium island 'layers' and named as Ge-DLC film, was prepared on the germanium substrate by ultraviolet laser. The Ge-DLC film had almost same surface roughness as the pure DLC film. Hardness of the Ge-DLC film was above 48.1GPa, which was almost the same as that of pure DLC film. Meanwhile, compared to the pure DLC film, the critical load of Ge-DLC film on the germanium substrate increased from 81.6mN to 143.8mN. Moreover, Ge-DLC film on germanium substrates had no change after fastness tests. The results showed that Ge-DLC film not only kept high hardness but also had higher critical load than that of pure DLC film. Therefore, it could be used as practical protective films. [ABSTRACT FROM AUTHOR]

Ba xSrTiO3 () (BST) thin films were prepared on LaSrNiO4 (LSNO)/SrTiO3 (STO) structure by combinatorial pulsed laser deposition (comb-PLD). The capacitances of the Au/BST/LSNO capacitors exhibited strong frequency dependence especially when the applied frequency was higher than 10kHz. On the basis of an equivalent circuit model, we presented a theoretical simulation of the relationships between capacitance and frequency for the capacitors with different electrode serial resistances. Based on the fitting results, the observed strong frequency dependence of the measured capacitance at high frequency in our study could be ascribed to the large serial resistance of 750 for oxide electrode LSNO. Further simulation studies found that large serial resistance (1000 ) could result in an apparent deviation from the intrinsic dielectric properties especially at high frequencies (100kHz) for capacitors with capacitances above 1nF. Our results provide useful information for the design of all-oxide electronic devices. [ABSTRACT FROM AUTHOR]

Tungsten thin films were prepared by pulsed laser deposition (PLD) technique on glass substrates placed at the angles of 0 to 70 with respect to the target surface normal. Rutherford backscattering Spectrometry (RBS) analysis of the films indicated that about 90% of tungsten material flux is distributed in a cone of 40 solid angle while about 54% of it lies even in a narrower cone of 10 solid angle. Significant diffusion of tungsten in glass substrate has been observed in the films deposited at smaller angles with respect to target surface normal. Time-of-flight (TOF) measurements performed using Langmuir probe indicated that the most probable ion energy decreases from about 600 to 91eV for variation of from 0 to 70. In general ion energy spread is quite large at all angles investigated here. The enhanced tungsten diffusion in glass substrate observed at smaller angles is most probably due to the higher ion energy and ion assisted recoil implantation of already deposited tungsten. [ABSTRACT FROM AUTHOR]

Bi4Ti3O (BIT) and BiNdTi3O (BNT) thin films were deposited on Pt/Ti/SiO2/Si (100) substrates using pulsed laser deposition. The surface morphologies, ferroelectric domain structures and polarization switching were investigated by atomic force microscopy (AFM) and piezoelectric force microscopy (PFM). The phase and amplitude images of PFM show that the BIT and BNT thin films have clear domain structures. Comparison of the surface morphologies and domain structures indicates that the grain boundaries limit the shape of domain and affect the domain structure. The micro-electromechanical performance was characterized by the effective piezoelectric coefficient of the thin films. The result shows that the maximum effective value (100 pm/V) of BNT thin film is larger than that of BIT thin film (30 pm/V). This can be ascribed to BNT thin film with a preferred growth direction of -axis, resulting in effective enhancement of . Besides, all the thin films exhibit good optical transmittance in the range of 500-800 nm and the optical band gaps increase from 3.43 eV to 3.52 eV due to Nd doping. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of argon introduction on the structural and physical properties of Ba0.6Sr0.4TiO3 (BST) films, epitaxial BST films have been grown by pulsed laser deposition (PLD) on (001) oriented Nb-SrTiO3 (STON) substrates in the ambient gas of pure oxygen and the mixture of argon and oxygen, respectively. The atomic force microscopy (AFM) reveals that the sample deposited in the mixture of argon and oxygen has a bigger grain size than that deposited in pure oxygen. The dielectric properties of two BST films have been investigated using the Pt/BST/STON parallel plate capacitors. The tunability and the figure of merit (FOM) of the BST film deposited in the mixture gas are about 41% and 7.07 at a DC bias voltage of 8 V at room temperature, which are better than 32% and 4.51, for BST film deposited in pure oxygen. On account of the introduction of argon, the leakage current density of the BST film deposited in the mixture gas has fallen by almost five times, and the leakage current mechanism is both in accordance with ohmic conductive mechanism. [ABSTRACT FROM AUTHOR]

Pulse laser deposited thin films of TiN are irradiated by 1 MeV carbon (C+) ions beam for various doses ranging 0.4 to 2.8 × 1014 ions/cm2. Atomic force microscopy (AFM) analysis reveals the formation of hillocks like structures after ion irradiation. X-ray diffraction (XRD) investigations show that the film crystallinity increases for lower doses ranging from 0.4 to 1.2 × 1014 ions/cm2 and decreases for higher doses (2 to 2.8 × 1014 ions/cm2) of ions. No new bands are identified from Raman spectroscopy. However, a noticeable change in microhardness has been observed. The hillock densities as well as hardness are strongly dependent upon ion dose. [ABSTRACT FROM AUTHOR]