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Here, we report on the fabrication of Nb-doped SrTiO3 (SrTi0.90Nb0.10O3) thin films of various thicknesses (50 to 375 nm) using pulsed laser deposition. X-ray diffraction studies reveal that the SrTi0.90Nb0.10O3 films are polycrystalline in nature with texturing along the (110) direction. XPS studies show that Nb replaces Ti confirming B-site doping. We demonstrate that the band gap of the SrTi0.90Nb0.10O3 thin films exhibit a blue shift of ~ 340 meV with decrease in thickness from 375 to 50 nm. Impedance spectroscopic studies at various temperatures (30–150 °C) suggested that the dc conductivity of the films increases with increase in temperature suggesting a thermal activation of niobium donor in the films. [ABSTRACT FROM AUTHOR]

Atomically thin molybdenum disulfide (MoS2) thin films are a promising avenue of investigation due to its potential applications in modern nanoscale electronic devices. In this work, we present a systematic investigation of the effect of in situ argon-ion sputter etching on the core-level X-ray photoelectron spectroscopy (XPS) of the chemical vapor-deposited MoS2 thin films. Raman spectroscopy of the MoS2 reveals that the thin films are tri-layer samples. Photoluminescence spectrum of the tri-layer MoS2 consists of A- and B-exciton emission peaks at 1.85 and 1.99 eV, respectively. The core-level XPS spectra of the Mo-3d and S-2p levels of the tri-layer MoS2 were investigated for various in situ sputter etch time. The as-grown and 6 s sputter-etched MoS2 sample exhibited Mo-3d spin–orbit doublets corresponding to + 4 oxidation state of Mo. For the sputter etch time beyond 40 s, the sample exhibited + 6 oxidation states of molybdenum suggesting the presence of thin molybdenum oxide at the interface between MoS2 and sapphire. We have also observed mid oxidation states like Mo5+, which is attributed to the argon-ion sputter etch-induced sulfur-deficient mixed S–Mo–O and sub-stoichiometric phases. [ABSTRACT FROM AUTHOR]

The ternary full Heusler alloy nanoparticle Fe2CrSi compounds were prepared using mechanical alloy method. The as-prepared sample was observed as amorphous in nature and further increases various annealing temperatures (like 700 °C, 800 °C, and 900 °C) in nitrogen gas atmosphere for 5 h in tubular furnace using quartz tube. X-ray diffraction studies confirmed the formation of Cu2MnAl-type structure instead of the conventional L21 disordered structure. Through Williamson-Hall plot (W-H plot), the uniform deformation model was used to get low value of strain-induced broadening. In the surface morphology, elemental composition studies were carried out using HRSEM with EDS. The presence of Fe2CrSi with the particle size of ~ 35 nm was also observed using high-resolution scanning electron microscopy and elemental composition study confirmed the presence of Fe, Cr, and Si. The magnetic properties of Fe2CrSi nanoparticles were studied showing ferromagnetic behavior and low coercivity of soft magnetic nature. Half metallic ferromagnetic Heusler alloys have wide range of applications from medical imaging to data storage for its profound performance on spintronics. [ABSTRACT FROM AUTHOR]

Here, 1 mol% Dy,Ce co-doped ZnO nanoparticles were synthesized via a simple, cost-effective combustion method which could produce large-scale products. The structure and phase purity of synthesized nanoparticles were shown by X-ray diffraction, selected-area-electron-diffraction patterns and Raman spectroscopy to be a hexagonal wurtzite structure with no secondary peaks. Spherical morphology was shown by field emission scanning electron microscopy and high-resolution transmission electron microscopy. The presence of dopants with elemental composition was authenticated by energy dispersive spectroscopy and elemental mapping. Enhanced reflectance in the visible region for Ce-doped ZnO samples was noted by diffuse reflectance spectroscopy. An increase in the bandgap for doped samples was indicated by the Kubelka–Munk function. Significant visible luminescence was observed, which varied with different excitations. The room-temperature weak ferromagnetic behaviour of 2 mol% Ce-doped ZnO and distinct paramagnetic behaviour of 1 mol% Dy,Ce co-doped ZnO was detected using vibrating sample magnetometry. [ABSTRACT FROM AUTHOR]

Fe2CoSi based Heusler alloy thin films are deposited on single crystal Si (111) substrate at different substrate temperatures varying from room temperature to 600 °C using ultrahigh vacuum DC magnetron sputtering. Structural analysis of the prepared thin films is carried out using GI-XRD measurement and it conform ordered L21 crystal structure of the films deposited at 450 °C and above. The atomic force microscopic (AFM) images of Fe2CoSi thin films exhibiting 3D-like growth on Si (111) substrate at varying temperatures. The magnetic property of the thin films is studied using vibrating sample magnetometer (VSM). At 450 °C of substrate temperature, the prepared thin film exhibits high saturation magnetization (Ms = 948 emu/cc) and low coercivity (Hc = 8 Oe). The self-energy magnetization of the film and its own field is very high, when the temperature of the substrate was maintained at 450 °C and switching field ratio for this film was obtained as ~ 0.9 due to its high crystallinity and atomic ordering. The electrical property of Fe2CoSi thin film is investigated using four-probe technique and a positive magnetoresistive behavior was observed for thin film deposited at a substrate temperature of 450 °C which indicates the possible half-metallic nature at room temperature. The enhanced magnetic and electrical properties obtained for the thin film prepared at 450 °C substrate temperature is highly suitable for spin -based device applications. [ABSTRACT FROM AUTHOR]