Nanoparticles with general formula CoFe2-xRExO4 (RE = Yb, Dy, Gd; x = 0.0–0.3) were synthesized by the co-precipitation and heat treated for potential application in magnetic hyperthermia. The influence of RE doping on structural, magnetic and thermal properties has been investigated. The RE cations enter the spinel lattice as detected by X-ray diffraction. Thermal treatment leads to thermodynamically

Temperature dependence of mechanical and thermodynamic properties of refractory high entropy alloys Ti(25+x)Zr25Nb25Ta(25-x) (x ≤ 20) are studied from ab initio quasi-harmonic Debye-Grüneisen model, and the influences of substitution of Ti for Ta are emphasized. The substitution of Ti for Ta results in the significantly reduced densities and the apparently enhanced specific elastic properties of T

SeO2 based glass system of the composition 39 PbO–(60-x) B2O3– xSeO2:1.0 Yb2O3 (with 10 ≤ x ≤ 50) were synthesized. Analysis of the results of structural studies revealed that the glass network consists of [SeO4]2− and [SeO3]2− units; the studies further indicated an increasing fraction of [SeO3]2− units and decreasing concentration of [SeO4]2− groups with increase of SeO2 content. Optical Absorption

Linear spin-wave approximation and Green's function were used to study the dependence of spin wave resonance (SWR) frequency in a ferromagnetic film considering the external magnetic field, surface anisotropy, number of atomic layers, nearest and next nearest neighbor interaction. A systematic study of the SWR frequency as a function of external magnetic field, surface anisotropy, and next nearest

Plasmonic metamaterials have recently received increasing attention due to their favorable optical and electrical properties. The physics of the interaction between plasmonic metamaterials and lasers are rich and open opportunities for applications, such as sensing, imaging and photovoltaics. Here, we investigate the mechanism of the interaction between Ag nanorod arrays and nanosecond (ns) pulsed

The structure, transition properties, and hydrostatic pressure (p) and magnetic field (B) dependence of transition temperatures and operation-temperature window (ΔT, defined as the temperature range of martensitic transition) were investigated in Ni53Mn21Ga26 alloy. The results reveal that all the transition temperatures and ΔT increase almost linearly with increasing magnetic field and pressure. Particularly

Plasmonic nanostructured silver silica at an optimum volume ratio of silver silica and constant concentration of silver nanoparticles (AgNPs) was successfully synthesized by the sol-gel technique for surface-enhanced Raman scattering (SERS) application. Transmission electron microscopy (TEM) images confirm that the optimum ratio of the nanostructures consists of SiO2 particles partially penetrated

This paper reports the details of fabrication of aluminum-doped zinc oxide (AZO) thin films on Corning glass substrates by pulsed laser deposition technique at different laser ablation fluences: 8.75, 17.5 and 35 J/cm2. The influence of laser fluence on the structural, optical and electrical properties of the prepared thin films is analyzed and discussed. X-ray diffraction pattern of AZO thin film

We report the band structure calculations of rare earth based half Heusler LuNiSb compound for thermoelectric performance. A narrow energy gap of 0.227 eV is opened using TB-mBJ approximation. The value of Seebeck coefficient 288 (μVK −1) at room temperature using mBJ scheme is quite large as compared to the experiment as well as well known thermoelectric material PbTe at same temperature. The observed

The study aims at assessing the elastic and electronic properties of o-Fe2C, h-Fe3C, t-Fe5C2, m-Fe5C2 and h-Fe7C3 compounds using first-principles calculations based on the density functional theory. A comprehensive study of elastic constants and moduli shows that five compounds fulfill mechanical and dynamic stability conditions and are ductile. The Young's and shear modulus for o-Fe2C, h-Fe3C, t-Fe5C2

Valley Hall topological insulators (VHTIs) in condensed matter physics have been recently extended to acoustic systems and have attracted great attention. However, the current acoustic topological insulators (ATIs) are mainly based on the mechanism of Bragg scattering in phononic crystals. Their demonstration and application are limited by factors, such as non-tunable structure and lattice-scale size

The influence of high pressure on mechanical, electronic, and thermoelectric transport properties of TbT4P12 (T = Fe, Ru, Os) have been studied. All the calculations were performed using the full-potential linearized augmented plane wave method, as implemented in the WIEN2k code. The exchange-correlation energy is obtained using generalized gradient approximation due to Perdew-Burke-Ernzerhof for solids

The lattice dynamics of the ordered Au/Cu(111) surface alloy system are investigated, in particular for the low-coverage ordered Cu(111) -Au(3×3)R30° surface alloy structure. The computations are developed using the phase field matching theory (PFMT) and the Green's functions (GF) formalism. Dispersion branches for surface phonons and resonances along the directions of high symmetry ΓM¯, MK¯, and KΓ¯

We study the thermoelectric properties of zigzag-edge phosphorene nanoribbon with N chains (N-ZPNR) under a perpendicular electric field (PEF). By adopting the tight-binding Hamiltonian combined with the nonequilibrium Green’s function method, it is demonstrated that the maximum value of the Seebeck coefficients for both 40- and 41-ZPNRs can reach 4 mV/K. Interestingly, there is an even–odd effect

In this paper, we have successfully controlled the thermoelectric properties of copper nitride (Cu3N) thin films by optimizing the post growth nitrogen gas flow time. During thermal evaporation growth of Cu3N thin films, pure copper power (0.12 g) was evaporated on soda lime glass substrate. The boat temperature and nitrogen gas flow rate were fixed at 1010 °C and 100 sccm respectively in horizontal

The transfer matrix method is used to investigate the reflectance properties in a symmetric defective annular photonic crystal (APC) containing semiconductor, high-Tc superconductor and a radial defect layer. Numerical results offer many noteworthy features that can be very useful in designing optical devices. In this regard, the geometric effects of alternate layers on the optical reflectance of our

We investigated the mechanism of magnetic noise due to both surface and bulk impurities. For surface noise, we apply the Langevin method to spin fluctuation theory to calculate the noise for paramagnetic surface impurities absorbed in a thin layer of water. We find that the mechanisms generating noise are spin flip and spin precession which depend on impurity spin relaxation and spin precession time

The structural disorder degree of Ga-doped ZnO (Zn1−xGaxO, with x=0.005, 0.01, 0.02, and 0.03) ceramics was investigated by means of Raman spectroscopy analyzes at room temperature. The Raman spectra for Ga-doped ZnO samples exhibits both activated Raman modes for wurtzite and spinel structures. The asymmetry parameter, line-with, and Raman shift could be fitted to the Breit-Wagner-Fano (BWF) function

In this work, the Sr1-xCaxFe12-yZnyO19 (x = 0, 0.05, 0.1, 0.15; y = 0, 0.25, 0.5, 0.75) hexaferrite were prepared employing the sol-gel combustion method and their structural, magnetic and optical properties were investigated. The formation of the hexaferrite phase was confirmed in all the samples using the X-ray diffraction and Fourier transform-infrared spectroscopy measurements. The field emission

NiFe2O4 & NiFe1.925R0.075O4 (R = Lu, Yb & Y) samples conductivity response for alternating current (σac) in the high temperature region (300 K to 570 K), and for direct current conductivity (σdc) response in the temperature range 80 K–300 K were investigated. For all the investigated samples σac increases with raising frequency owing to transfer of charge carriers at the two octahedral sites containing

In this paper, we investigate the thermoelectric transport coefficients namely the Seebeck coefficient, the electrical conductivity, the electronic thermal conductivity and the lattice thermal conductivity using first-principles calculations in density functional theory. We also estimate the figure-of-merit for both intrinsic as well as extrinsic low-buckled monolayer silicene. Using Electron-Phonon

In this work, a broad investigation on the optical parameters of TPD:Alq3 composite thin films is reported. The films are prepared from different solution-processed mixtures and are deposited onto the quartz substrate in order to measure their optical response with UV–Vis–NIR spectrophotometer. Results showed that the non-dispersive refractive index and dielectric constant of TPD was increased from

The magnetic properties and electronic structures of SMOn/LAOm are investigated by density functional theory calculations to reveal the magnetic ground states and novel interfacial spin transport properties. Both n-type LaO/MnO2 and p-type SrO/AlO2 interface show metallicity, and the density of states of Mn and O play the crucial role. It is demonstrated that we can tailor the electronic properties

We report on the thermoelastic properties of Ni2MnGa shape-memory alloys across the martensitic to austenitic phase transition using the time-resolved pump-probe photothermal mirror technique. Quantitative information on the thermo-mechanical characteristics of the sample are obtained and compared to specific heat measurements and differential scanning calorimetry (DSC) analysis. The thermal diffusivity

A comprehensive review and analysis of experimental measurements of the conductivity σm(ϕ), the thermal conductivity λm(ϕ) and the magnetic permeability μm(ϕ) in various composites/mixtures is presented. The Two Exponent Phenomenological Equation TEPPE is a function of the volume fraction (ϕ) which has five parameters, including the percolation exponent t, is used to analyse the results. In bonded/contiguous

In this work, we have investigated theoretically the impact of intense laser, electric and magnetic fields on the linear and nonlinear optical properties of a quantum well heterostructure containing triple parabolic barriers (GaAs/AlGaAs). Within the framework of the effective-mass and parabolic band approximations, we have computed the confined lowest energy levels and their corresponding densities

The beam waist relative variation (BWRV) method known as a Z-scan based technique is used to demonstrate its feasibility in characterizing the thermal effects induced by a continuous laser beam in different materials. A study of several classical solvent-based solutions (water, ethanol, methanol …) is carried out before introducing the extension of the BWRV method to laterally map the tested sample

The impact of Ni doping on the morphological, electrical and dielectric properties in a polycrystalline sample of YMn0.4Fe0.6O3 was investigated. SEM analysis reveals that grain size increases with the rise of Ni concentration in YMn0.4Fe0.6-xNixO3 (x = 0, 0.05, 0.075 and 0.1) nanoparticles up to x = 0.075. The DC conductivity results indicate that all samples exhibit semiconductor behavior over the

In this study, the hydrothermal method is used for the synthesis of Vanadium pentoxide (V2O5) microstructure. Analysis stands for the growth of microstructure in only the orthorhombic phase. The dot pattern in SAED image shows the crystalline nature of microstructure. Raman analysis shows the layered structure of V2O5. The morphological study of V2O5 shows the flower-like microstructure formed by nanorods

Co: ZnS (0, 6, 12 and 18 at. -%) nanostructures are mounted on glass substrates by chemical bath deposition (CBD) technique. X-ray diffraction (XRD) analysis shows cubic structure. Compositional study using X-ray photoelectron spectroscopy (XPS) establishes chemical states of Zn2+, S2−, Co2+ and some impurity elements such as C and O. Morphological study reveals the granular shape of the as-grown films

Noble metal Pt with the face-centered-cubic structure is distorted to tetragonal and orthorhombic structures in order to mimic thin films grown on flexible substrates and bending. The electronic structures from the fully relativistic treatment of the kinetic terms were obtained and followed by projecting the extensive states into the localized Wannier orbitals with a minimum basis. The spin Hall conductivity

A simple sonochemical hydrolysis was used to synthesize dysprosium (Dy) doped titania (TiO2) nanopowder. The microstructure results have been confirmed the amorphous structure with high roughness-surface morphology of the undoped TiO2 sample. Whereas, Dy-doped TiO2 samples are in anatase phase with small crystallite size ~5.5 nm. The optical energy gap exhibited close variations with Dy content that

In this article, the estimation of current transfer length (CTL) and electric field of MgB2 (M) monofilamentary superconducting wires for various metals which are used as a sheath and barrier with their different cross-sectional compositions of superconducting core/barrier/sheath are studied. Among the studied superconducting wires, the least CTL values are estimated for M/Ti/Ta (0.48 mm), M/Ti/Nb

A study has been performed by investigating the variation of absorbance and photoluminescence intensity of the perovskite as a function of precursor mixing ratios at room temperature. In this study we used CH3NH3SnCl3 perovskite wherein CH3NH3Cl and SnCl2 solutions are the precursors. These two precursors are mixed with ratios of 3:1, 1:1 and 1:3. XRD, UV–Vis absorption and photoluminescence studies

We report on the synthesis of polycrystalline samples of heavy-fermion compound Ce3PtIn11 and the characterization of their structural and low-temperature physical properties. In good agreement with the data previously obtained for single crystals, the polycrystals also form with a tetragonal crystal structure (space group P4/mmm, Z = 1) with the lattice parameters a = b = 4.6934(7) Å, and c = 16.8306(3)

The thermally induced increase in optically stimulated luminescence of super-luminous Sr4Al14O25:Eu,Dy is reported. To isolate this thermal assistance to emission, which is otherwise obscured by high intensity transient emissions, stimulation was done using 870 nm infrared light. The optically stimulated luminescence intensity measured between 20 and 200 °C goes through a peak. The profile is reproducible

Nanocomposites of cobalt ferrite (CoFe2O4) were synthesized using chemical co-precipitation route. For preparing the nanocomposites, cobalt ferrite was combined with strontium ferrite (C/S-1/1) and with barium ferrite (C/B-1/1) in equal weight ratio of 1:1. Dual phase Rietveld refinement procedure was employed for phase analysis of the specimens. Electrical transport properties were investigated within

It is experimentally shown that the electrolysis of silver salt in silicate nanoporous glasses (NPGs) with interconnecting pores, having average sizes of 25 nm, makes possible to fabricate metal-glass nanocomposites. Silver component of nanocomposites consists of fractal microbranches, which, in turn, consist of silver nanowires. By iodizing silver nanowires can be transformed to AgI nanowires. Absorption

In present work, the strain effect on the electronic, optical and thermoelectric properties of the Boron phosphide (BP) monolayer have been systematically investigated using first-principles calculations. Simulations show that the single layer at hand is a direct semiconductor possessing a K−K band gap of 0.910 eV. This parameter increases when switching the strain nature from compressive to tensile

Magnetic measurements confirmed that the Co2MnSi Heusler compound is a superior ferromagnetic material to the Co2MnGa Heusler compound. The Co2MnGa Heusler compound showed a saturation magnetization of 81.3 emu/g and a Curie temperature of 700 K, while the Co2MnSi Heusler compound exhibited both a high saturation magnetization of 130 emu/g and a high Curie temperature of 1015 K. Thermoelectric measurements

The Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) ceramics were successfully prepared by the sol-gel process and sintered at 1420 °C. The effect of sintering times (2, 4 and 6 h) on structural, microstructural, electric properties, energy storage, and electrocaloric effect was systematically examined. X-ray diffraction (XRD) results show that all the samples crystallize in the pure perovskite structure. The morphotropic

This study presents efficient photocatalytic degradation of tetracycline (TC) via impregnation of Cu2O nanoparticles on TiO2 nanosheets/reduced graphene oxide nanocomposites. Different techniques such as PXRD, UV–Vis DRS, TEM, FESEM/EDX, Raman spectroscopy and N2 physisorption were employed to identify synthesized samples. The results of PXRD and Raman analyses indicated that TNs had a pure anatase

In current research work we have able to enhanced the thermoelectric power generation ability of ZnO using two different methods simultaneously i. e alloying with Al atoms and post growth annealing method. ZnAlO alloy having different Al concentration (1, 1.5 and 2%) was converted into pallets after mixing Al and zinc oxide powders using hydraulic press having 13 tons pressure. The prepared pellets

Here we use a simple method of dip-coating catalyst to prepare single walled carbon nanotube (SWCNT), and study its cathode field emission property. The field emission performances of SWCNT films are not significantly different when the hydrogen flow quantities are in the range of 10–50 sccm. SWCNT prepared by different catalyst are also used as cathode to test field emission performance. SWCNT fabricated

The environmental problems have been arisen and the importance of electronic, optical and thermoelectric applications is being well re-recognized. Orthorhombic structure of perovskite materials ARhO3 (A = Bi, Lu) have been gaining interest recently due to their unique and tunable electronic and crystal structure. First principle calculations reveal a semiconductor behavior for both materials. Band

Organic-inorganic hybrid perovskites have been receiving considerable attention due to their excellent performances. However, the pollution of the lead element and the instability under strong light and high temperatures are still problems to be solved. In this work, we studied the structure and photoelectrical properties of Cs and Zn co-doped organic-inorganic hybrid perovskite by first-principles

Gadolinium aluminum garnet is a compound with cubic structure composed of Al–O octahedron and Al–O tetrahedron. The chemical formula is Gd3Al5O12 (GdAG). In the field of optics, GdAG is an excellent matrix material, which has led researchers to explore in the direction of phosphors, scintillators and solid-state lasers. In view of many advances in recent years, the recent findings of GdAG and its derivatives

La3Si6N11:Ce3+ (LSN:Ce3+) phosphor has attracted widespread attention in the field of high-power white light-emitting diodes as it can be effectively excited by blue LED chip and exhibits excellent thermal quenching. To improve the emission intensity is always the critical objective of La3Si6N11:Ce3+. In this paper, the strategy by combining CeO2 and CeN as cerium sources of the activator was developed

In this work, we found that the electron-phonon interaction (EPI) is dependent on the surface roughness. Simulations of Resonance Raman Spectroscopy (RRS) spectra, show that the Fano asymmetry parameter q, decreases as the Mean Surface Roughness (MSR) increases. They also make it clear, that the magnitude of the EPI strength increases with increasing roughness. Our results also show that the EPI along

Asymmetric devices are fabricated by cramming the active material Co3O4/C composite (positive electrode) with activated carbon (negative electrode). Devices are examined under aqueous and gelled electrolyte. The theoretical model is adopted to study the charge storage mechanism in two devices. It has been observed that the capacitive and diffusion-controlled contribution of electrode material is affected

Band structures of armchair graphene nanoribbons (AGNRs) under crossed external fields are calculated within the tight-binding model. Magnetic field reduces energy-gap and flattens energy dispersions of band-edge states. Electric field strongly distorts energy dispersions leading to a reduction of energy-gap, a shift in band-edge states and many local maxima and minima. The complex dielectric function

Polarimetric neutron tomography provides a powerful tool for direct visualization of magnetic fields in the bulk of matter. However, the measurable field strength has been severely restricted because neutron spin precession angles have to be limited below π due to the phase wrapping problem. In this article we show that in most cases the spin precession limit can be extended by identifying and correcting

This paper presents different methodologies for the preparation of Fe2O3@SiO2 nanoparticles (composites) and their characterization. The composite nanoparticles were prepared directly from rice husks. Two methodologies were used, (i) impregnation with an ionic iron solution of rice husks followed with a thermal treatment and (ii) impregnation of the pre-calcinated and lixiviated rice husks. In both

The synthesis of nickel potasium ferrite (Ni0·8K0·2Fe2O4) nanoparticles with the doping of Monovalent K1+ ions has been synthesized by sol-gel auto combustion method. Differential Thermal Analysis (DTA) was performed to analyze the phase formation of the prepared sample. The crystal phase formation has been confirmed by employing the XRD (X-ray diffraction) technique. The crystallite size and Strain

We defeated the postulate that Fano resonances prevail in molecular wires connected to pendent groups, and they perish in molecules with intercalating moieties. Our theoretical calculations prove the occurrence of Fano resonance in metal-incorporated molecules— porphyrin— only if a segment of the molecule undergoes a certain in-plane deformation. The resulted Fano resonance can be induced by the strength

Polycrystalline bulk samples of La0.7-x BixSr0.3MnO3 (x = 0.35 and 0.40) manganites have been subjected to high energy planetary ball milling to prepare nanoparticles by using the top-down approach. A significant drop in the particle size has been observed with an increase in milling time. The high temperature magnetic transitions get broader and suppressed while the low temperature maxima in magnetic

In this work, Sm24.6Co50Fe17·4Cu5·7Zr2.3-xHfx (x = 0–2.0) ribbons and magnets were prepared by melt-spinning method and spark plasma sintering (SPS) technique. The magnetic properties of the melt-spun ribbons with Hf addition are much higher than those of the Hf-free ribbons in the temperature range of 300–400 K. The optimal comprehensive magnetic properties of ribbons and isotropic magnets were obtained

Diamond quantum dots (diamond QDs) have attracted great interest on account of their excellent physical and chemical properties. Here, we synthesized the diamond QDs 2–8 nm in diameter through alkaline assisted oxidation at room temperature. This composite method fairly original, simple, low-cost, and eco-friendly. High-resolution TEM, XRD and XPS confirm the diamond structure of the synthesized nanocrystals