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The deployment of fifth-generation mobile network (5G), beyond 5G and sixth-generation mobile network platforms encounters challenges of blockage, interference, and path loss in radio mobile environments. Metasurfaces provide a promising solution to address these limitations. In this paper, we present a methodology for developing ultrathin flexible metasurface-based frequency selective surfaces (FSSs). Our approach combines thermal evaporation for metallic thin films with a macroscopic metasurface mask (something analogous to screen-printing but using thermal evaporation instead of inks). As a proof of concept, we fabricate a sub-6 GHz metasurface-based FSS using gold deposition on a flexible polyethylene terephthalate substrate. Experimental results are validated through numerical full-wave simulations using COMSOL Multiphysics and equivalent-circuit model simulations. The metasurface operates within the primary frequency band utilized in 5G networks (3–5 GHz), indicating its potential applicability across a wide range of flexible, conformal, and wearable devices. The fabricated FSS can be installed on surfaces of any shape, such as flat or curved windows, as well as on walls or other external surfaces. This methodology offers practical solutions for wireless communications and enhancing signal transmission in diverse environments. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance (SPR) conventionally occurs at the interface of a thin metallic film and an external dielectric medium in fiber optics through core‐guided light. However, this work introduces theoretical and experimental evidence suggesting that the SPR in optical fibers can also be induced through light scattering from Au nanoparticles (NPs) on the thin metallic film, defined as nanoparticle‐induced SPR (NPI‐SPR). This method adheres to phase‐matching conditions between SPR dispersion curves and the wave vectors of scattered light from Au NPs. Experimentally, these conditions are met on an etched optical fiber, enabling direct interaction between light and immobilized Au NPs. Compared to SPR, NPI‐SPR exhibits stronger field intensity in the external region and wavelength tuning capabilities (750 to 1250 nm) by varying Au NP diameters (20 to 90 nm). NPI‐SPR demonstrates refractive index sensitivities of 4000 to 4416 nm per refractive index unit, nearly double those of typical SPR using the same optical fiber configuration sans Au NPs. Additionally, NPI‐SPR fiber configuration has demonstrated its applicability for developing biosensors, achieving a remarkable limit of detection of 0.004 nm for thrombin protein evaluation, a twenty‐fold enhancement compared to typical SPR. These findings underscore the intrinsic advantages of NPI‐SPR for sensing. [ABSTRACT FROM AUTHOR]

Combination of high quality cavity such as glass microsphere and emitting nano-particle coating layers can create novel strongly emitting devices. Herein, we demonstrate an erbium-doped silica microsphere coated by dual-emission carbon quantum dots, which have the sizes of 3–5 nm, emitting green up-conversion with narrow line-width green light at wavelength of 537 nm. The dual-emission carbon quantum dots fabricated by hydrothermal process and have luminescent emission wavelengths in the range of 410–550 nm. The carbon quantum dot coated erbium silica microsphere is pumped at wavelength of 976 nm through the optical fibre on which microsphere attached on the tip. The dual-emission carbon quantum dot layers attributed to the strong green up-conversion light enhancement similar coated noble metallic thin films, however the light enhancement from dual-emission carbon quantum dot coated erbium silica microsphere depended on the thickness of coating layers. This result is useful for making visible emitting micro-devices and photonic integrated circuits. [ABSTRACT FROM AUTHOR]

The calculation of the activation energy helps to understand and to identify the underlying phenomenon of oxidation. We propose a new method without any a priori hypothesis on the oxidation law, to retrieve the activation energy of partially and totally oxidized samples subject to successive annealing. The method handles the uncertainties on the measurement of metal and oxide thicknesses, at the beginning and at the end of the annealing process. The possible change in oxidation law during annealing is included in the model. By using an adapted Particle Swarm Optimization method to solve the inverse problem, we also calculate the time of final oxidation during the last annealing. We apply the method to successive annealings of three samples with initial nanometric layers of copper, at ambient pressure, in the open air. One, two and three successive laws are recovered from experimental data. We found activation energy values about 105–108 kJ mol − 1 at the beginning of the oxidation, 76–87 kJ mol − 1 at the second step, and finally 47–59 kJ mol − 1 in a third step. We also show that the time evolution of copper and oxide thicknesses can also be retrieved with their uncertainties. [ABSTRACT FROM AUTHOR]

We fabricated terahertz (THz) wave emitters from high-temperature superconductor Bi 2 Sr 2 CaCu 2 O 8 + δ (Bi2212) single crystals annealed under oxygen gas ( O 2) flow and nitrogen gas ( N 2) flow conditions. To better understand the annealing effects of the crystal for the device, we evaluated both device properties and a c -axis lattice constant using x-ray diffraction. Compared to the N 2 -annealed sample, the O 2 -annealed sample shows higher critical current in the current–voltage characteristics and no clear emission. In addition, multiple hysteresis loops were observed above 75 K. Based on the x-ray diffraction measurements, it is suggested that the presence of multiple hysteresis loops observed in the I–V characteristics of the O 2 -annealed sample is caused by the existence of layers that have varying levels of oxygen content along the c -axis direction of the crystal. The formation of these layers is attributed to the deposition process of metallic thin films during the device fabrication procedure. This result indicates that the Bi2212 crystal surface of the O 2 -annealed sample is more sensitive than that of the N 2 -annealed one. The information is useful for preparing the Bi2212 crystals for THz-wave emitting devices. [ABSTRACT FROM AUTHOR]

Fiber-reinforced polymeric composites have been extensively used in different industrial applications because of their excellent mechanical and other properties but have lower tolerance levels for fire and lightning damage. The thermal, mechanical, and electrical conductivity of these composites can be substantially increased using some thin metallic films for higher fire resistance. The objective of this study was to develop fire-retardant fiber-reinforced composites using modified resins and metallic copper (Cu) thin films and test and characterize the mechanical and thermal properties of these prepared composites. Standard hand wet layup process was used to manufacture composite panels, and then the flame retardant and other physical and chemical properties were determined before and after resin modification and surface metal film coatings. These modified resins and the conductive metallic films of the composite provided superior flame retardancy and higher mechanical strength. The prepared composite panels made from modified epoxy via 9,10-dihydro-9-oxo-10-phosphaphenanthrene-10-oxide (DOPO) inclusion and with metallic surface coatings passed the UL-94 vertical flame testing with a V-0 rating. This composite achieved an average flexural strength of 344.2 MPa, a mean tensile strength of 400.82 MPa, and a shear strength of 6.54 MPa for single lap shear joint studies. Fractography results also show better bonding of the matrix and fiber with no significant damage. This study may open new opportunities in various composite industries. [ABSTRACT FROM AUTHOR]

There is a growing need for precise and rapid detection methods in fields such as biomedical diagnostics, environmental monitoring, and chemical analysis. Surface plasmon resonance (SPR) sensors have been used for the detection and quantification of a wide range of analytes, including biomolecules, chemicals, and gases, in real-time. Despite the promising capabilities of SPR sensors, there remains a gap in creating a balance between having a large enough area to capture a significant number of analytes for detection and being small enough to ensure high sensitivity. This research aims to explore the design of a D-shaped SPR-based optical fiber sensor, focusing on the use of copper, gold, and silver thin films at optimized width and thickness of 10 µm and 45 nm, respectively, to improve the sensor's performance. Employing a computational approach, this study examines the influence of the optimized width and refractive indices of metallic films on the sensor's characteristics. The 10 µm width of the metallic thin film has been found to produce an optimal balance between the sensitivity and the dynamic range of the sensor. Leveraging on the ratio of the real and imaginary parts of the dielectric constant of the thin film metal provides insight into the optical properties and sensitivity at certain wavelengths. Within an analyte refractive index range of 1.37–1.42 and a wavelength range of 650–1200 nm, results indicate that silver outperforms gold and copper at the optimized width with a wavelength sensitivity, and detection accuracy of 12,300 nmRIU−1, and 3.075, respectively. By optimizing the width of the metal thin film at 10 µm, a highly sensitive D-SPR is designed, allowing for enhanced sensor detection capabilities for a wide range of bioanalytes. [ABSTRACT FROM AUTHOR]

The growing interest in the growth and study of thin films of low-dimensional metallic delafossites, with the general formula ABO2, is driven by their potential to exhibit electronic and magnetic characteristics that are not accessible in bulk systems. The layered structure of these compounds introduces unique surface states as well as electronic and structural reconstructions, making the investigation of their surface behavior pivotal to understanding their intrinsic electronic structure. In this work, we study the surface phenomena of epitaxially grown PtCoO2, PdCoO2, and PdCrO2 films, utilizing a combination of molecular-beam epitaxy and angle-resolved photoemission spectroscopy. Through precise control of surface termination and treatment, we discover a pronounced 3 × 3 surface reconstruction in PtCoO2 films and PdCoO2 films, alongside a 2 × 2 surface reconstruction observed in PdCrO2 films. These reconstructions have not been reported in prior studies of delafossites. Furthermore, our computational investigations demonstrate the BO2 surface's relative stability compared to the A-terminated surface and the significant reduction in surface energy facilitated by the reconstruction of the A-terminated surface. These experimental and theoretical insights illuminate the complex surface dynamics in metallic delafossites, paving the way for future explorations of their distinctive properties in low-dimensional studies. [ABSTRACT FROM AUTHOR]

Capturing a shear band in a metallic glass during its propagation experimentally is very challenging. Shear bands are very narrow but extend rapidly over macroscopic distances, therefore, characterization of large areas at high magnification and high speed is required. Here we show how to control the shear bands in a pre-structured thin film metallic glass in order to directly measure local strains during initiation, propagation, or arrest events. Based on the experimental observations, a model describing the shear banding phenomenon purely within the frameworks of continuum mechanics is formulated. We claim that metallic glasses exhibit an elastic limit of about 5% which must be exceeded locally either at a stress concentrator to initiate a shear banding event, or at the tip of a shear band during its propagation. The model can successfully connect micro- and macroscopic plasticity of metallic glasses and suggests an alternative interpretation of controversial experimental observations. The mechanisms of shear band initiation and propagation in amorphous metallic alloys is an open question of materials science. Here, the authors measure local strains around propagating shear bands and propose a model describing the plasticity of metallic glasses at different length scales. [ABSTRACT FROM AUTHOR]

In this article, we review recent developments in the experimental study of grain growth in nanocrystalline metallic thin films, emphasizing transmission electron microscopy-based imaging and orientation mapping techniques and highlighting useful experimental and data analytical frameworks for dynamic experiments. Studies of grain growth have fallen short of the scale required to fully characterize the coarsening process, and models still fail to fully capture the true behavior of grain growth in polycrystalline systems as they pertain to geometric, topological and crystallographic metrics. Moreover, existing grain growth studies are either coarse in time and temperature or otherwise limited in scope. Nevertheless, important observations such as the stagnation of thin film grain growth at a universal grain size distribution and the strong correlations between the grain boundary character distributions in thin film and bulk materials motivate larger-scale dynamic studies. Additionally, recent hardware and software advances have removed bottlenecks to large-scale and in situ data acquisition via (1) automated grain boundary segmentation in micrographs, (2) low thermal mass microelectromechanical systems and (3) integrated hardware-software drift correction and data management solutions. We argue that these innovations render thin films a key integrated experimental platform for the next generation of grain growth studies. [ABSTRACT FROM AUTHOR]

Nonlocal and quantum mechanical phenomena in noble metal nanostructures become increasingly crucial when the relevant length scales in hybrid nanostructures reach the few-nanometer regime. In practice, such mesoscopic effects at metal–dielectric interfaces can be described using exemplary surface-response functions (SRFs) embodied by the Feibelman d-parameters. Here we show that SRFs dramatically influence quantum electrodynamic phenomena – such as the Purcell enhancement and Lamb shift – for quantum light emitters close to a diverse range of noble metal nanostructures interfacing different homogeneous media. Dielectric environments with higher permittivities are shown to increase the magnitude of SRFs calculated within the specular-reflection model. In parallel, the role of SRFs is enhanced in noble metal nanostructures characterized by large surface-to-volume ratios, such as thin planar metallic films or shells of core–shell nanoparticles, for which the spill-in of electron wave functions enhances plasmon hybridization. By investigating emitter quantum dynamics close to such plasmonic architectures, we show that decreasing the width of the metal region, or increasing the permittivity of the interfacing dielectric, leads to a significant change in the Purcell enhancement, Lamb shift, and visible far-field spontaneous emission spectrum, as an immediate consequence of SRFs. We anticipate that fitting the theoretically modelled spectra to experiments could allow for experimental determination of the d-parameters. [ABSTRACT FROM AUTHOR]

The arbitrarily formed golden cluster systems were created in the gas state which has strong Resistive Switching (RS) behavior around ambient temperatures and makes these attractive candidates for the creation of electronics geared toward neuron categorization along with information analysis. The cluster-assembled nanotechnology coatings that are fully linked have an irregular shape that includes neuromorphic crystallographic flaws, interactions and frontiers of grains, highlighting the complex interaction among electromagnetic in mechanical elements. In this analysis, we conduct a thorough investigation of the electroforming procedure that is utilized in the creation of film that was the cluster assembled. The present research sheds light regarding the electroforming procedure's substantial influence on the complex relations among nanopores and the mesoscale layer formations and underlying neurological properties of resistance switches activities that ensure. The findings provide insight into a methodical oversight of electroforming operation and reveal its function in building distinct patterns at various sizes in films of cluster assembled. The discovery not only improves our understanding of the intricate relationships among architectural and electrical parts but it provides opportunities for designing neurological structures that are randomly constructed and customized over multiple information-handling applications. [ABSTRACT FROM AUTHOR]

Rock salt-type rare-earth monopnictides (REPn) attract much attention because of their extremely large magnetoresistance and topological properties. So far, most studies have been conducted on REPn bulk single crystals. Recent theoretical studies predicted that the topological properties of REPn can be developed by forming their ultrathin film or applying epitaxial strain. However, it has been difficult to grow highly crystalline REPn thin films due to the high vapor pressure of Pn, hampering the thin film growth at high temperature. Here, we grew highly crystalline (001)-oriented LaBi thin films by solid-phase reaction of a La/Bi multilayer precursor. The LaBi thin films showed metallic conduction and nonlinear Hall resistance, indicating the coexistence of electron and hole carriers, consistent with the intrinsically semimetallic nature of LaBi. [ABSTRACT FROM AUTHOR]

A high-infrared (IR) emissivity is required to dissipate heat effectively from high-temperature surfaces even in a near-vacuum environment. This radiative cooling capability is essential for the emissive layer of EUV pellicles operating under high vacuum conditions with increasing EUV source powers to ensure thermomechanical stability. We compute the IR emissivity of metal films by combining the classical oscillator model and DFT calculations. Based on the calculations, we predict a positive correlation between the electrical resistivity and IR emissivity of metal films, which is consistent with a recent experiment on Ru thin films. Our findings can provide a practical indicator for achieving high IR emissivity of metallic thin films based on electrical measurements. This emissivity–resistivity correlation can provide an effective way to search a large material space, and choose and synthesize a highly emissive layer of EUV pellicles. In this study, we computed the infrared absorbance of Ru thin films through the integration of the classical Drude-Lorentz oscillator model and DFT calculations. According to the Kirchhoff's law of thermal radiation, the IR absorbance is equal to the IR emittance. Based on the calculated results, we propose a positive correlation between IR emissivity and electrical resistivity. [ABSTRACT FROM AUTHOR]

Using a particle swarm optimization algorithm (a population-based stochastic optimization technique) combined with 3D finite-difference time-domain simulations, we inverse design periodic arrays of metallic nanoparticles on indium-tin-oxide electrodes and nanoholes in metallic thin films working as electrodes in P3HT (Poly(3-hexylthiophene-2,5-diyl)):PCBM ([6,6]-Phenyl C61 butyric acid methyl ester) organic solar cells to achieve the maximum short-circuit currents (J s c ). Nanohole-array electrodes have large optical losses, leading to a net reduction of J s c compared to a reference solar cell. On the other hand, nanoparticle arrays can lead to a significant enhancement of J s c of up to 20%. Detailed simulations show that this enhancement is caused by the grating coupling of the incident light to surface plasmon polaritons at the interface of the metal electrode and the hole transport layer, leading to the enhancement of the electromagnetic field in the organic blend. [ABSTRACT FROM AUTHOR]

Diffraction gratings have always been used to effectively couple optical radiation within integrated waveguides. This is also valid for plasmonic structures that support Surface Plasmon Polariton (SPP) waves. Traditional gratings usually excite SPP waves at the interface where they are located or, for thin metal nanostrips, at both interfaces. But reducing the thickness of the metal layer in the presence of a grating has the handicap of increasing the tunnelling of light towards the substrate, which means higher losses and reduced coupling efficiency. In this paper, we design and optimize novel gratings buried within the metallic thin films for selective coupling of SPP waves onto individual interfaces. Compared with traditional superficial gratings, the novel buried ones demonstrate higher efficiency and much lower residual tunnelling of light through the coupling structures. [ABSTRACT FROM AUTHOR]

A spectrophotometric method is demonstrated for refractive index and thickness determination of thin and ultrathin metallic films. The method involves a three-layer stack where the metallic layer of interest is deposited on an opaque Si wafer coated with SiO2. This stack creates oscillations in the reflectance spectrum, which are highly sensitive to the index of the metallic film, allowing precise determination of the index of layers down to 1 nm. Experimental index values are given for Ag and Au over the wavelength range of 370–835 nm. These results are correlated with Atomic force microscopy (AFM) images of the films, which reveal dramatic changes in structure for layers of different thickness. [ABSTRACT FROM AUTHOR]

The goal of the review is to analyse the main published results of the most systematic studies of changes in the structural-phase state, the physical and chemical properties of the metallic single- and multilayer thin films' systems after bombardment by the low-energy (<10 eV) inert-gas ions. Nanoscale film systems are obtained using two widespread physical methods: magnetron deposition and thermal resistive evaporation. The single-layer systems are based on such pure metals as Co, Cu, Ni, Pt, Nb, Ti, Fe, and W. The films deposited on the Si(100) substrate have thicknesses in the range of 25-700 nm. Multilayered thin films are fabricated based on the following combinations: Cu/Ni, Ni/Cu/Cr, Cr/Cu/Ni, and Ni/Cu/V with 25-30 nm thickness of each layer. The low-energy inert-gas ions' (Xe+, Ar+, Ne+, He+) bombardment with varying beam energy in the range of 200-10 000 eV and fluence in the range of 1015-1019 ions/cm2 are used. The ion bombardment-induced morphology, microstructure and chemical evolution of the polycrystalline thin films are studied using x-ray diffraction (XRD), secondary ion mass spectrometry (SIMS), Auger-electron spectroscopy (AES), electrography, transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), and tribological tests. Different physical mechanisms contributing to this evolution and their relation to theoretical models and experimental studies of the ion-induced thin films are discussed. [ABSTRACT FROM AUTHOR]

An antiferromagnetic metal with a two-dimensional triangular network offers a unique playground of intriguing magneto-transport properties and functionalities stemming from the interplay between conducting electrons and intricate magnetic phases. A NiAs-type CrSe is one of the candidates owing to alternate stackings of Cr and Se triangular atomic networks in its crystal structure. While the fabrication of CrSe thin films is indispensable to develop functional devices, studies on its thin-film properties have been limited to date due to the lack of metallic samples. Here, we report on the realization of metallic conductivities of CrSe thin films, which allows us to investigate their intrinsic magneto-transport properties. The metallic sample exhibits a co-occurrence of weak ferromagnetism with perpendicular magnetic anisotropy and antiferromagnetic behavior, indicating the presence of non-coplanar spin structures. In addition, control of the polarity and tilting angle of the non-coplanar spin structure is accomplished by a sign of cooling magnetic fields. The observed non-coplanar spin structure, which can be a source of emergent magnetic field acting on the conducting electrons, highlights the high potential of the triangular lattice antiferromagnet and provides a unique platform for functional thin-film devices composed of NiAs-type derivative Cr chalcogenides and pnictides. [ABSTRACT FROM AUTHOR]

Efficiently transforming CO2 into renewable energy sources is crucial for decarbonization efforts. Formic acid (HCOOH) holds great promise as a hydrogen storage compound due to its high hydrogen density, non‐toxicity, and stability under ambient conditions. However, the electrochemical reduction of CO2 (CO2RR) on conventional carbon black‐supported metal catalysts faces challenges such as low stability through dissolution and agglomeration, as well as suffering from high overpotentials and the necessity to overcome the competitive hydrogen evolution reaction (HER). In this study, we modify the physical/chemical properties of metal surfaces by depositing metal monolayers on graphene (M/G) to create highly active and stable electrocatalysts. Strong covalent bonding between graphene and metal is induced by the hybridization of sp and d orbitals, especially the sharp dz2 ${{d}_{{z}^{2}}}$ , dyz ${{d}_{yz}}$ , and dxz ${{d}_{xz}}$ orbitals of metals near the Fermi level, playing a decisive role. Moreover, charge polarization on graphene in M/G enables the deposition of another thin metallic film, forming metal/graphene/metal (M/G/M) structures. Finally, evaluating overpotentials required for CO2 reduction to HCOOH, CO, and HER, we find that Pd/G, Pt/G/Ag, and Pt/G/Au exhibit excellent activity and selectivity toward HCOOH production. Our novel 2D hybrid catalyst design methodology may offer insights into enhanced electrochemical reactions through the electronic mixing of metal and other p‐block elements. [ABSTRACT FROM AUTHOR]

Titanium carbide materials are introduced into manufacturing industries for the reinforcement and surface protection of base materials due to their substantial ability to withstand severe environments, which include sliding wear, corrosion, and mechanical failures. A thin film of titanium carbide (TiC) is coated onto brass and copper substrates using the radio frequency magnetron sputtering (RFMS) deposition method. The coating process is carried out at constant processing parameters, which include a sputtering power of 200 W, a temperature of 80 °C, a deposition time of 180 min, and an argon (Ar) gas flow rate at 10 standard cubic centimetres per minute (SCCM). The coating, together with the base materials, is modelled and its behaviours are simulated using ANSYS Workbench R19.2 Academic, supported by Mechanical APDL solver for nonlinear finite element analysis (FEA). The deformation, equivalent stress–strain characteristics, and elastic–plastic properties of the coating are determined at applied loads of 60 N and 25 N and coefficients of friction (CoF) of 0.25 and 0.38 for the thin film deposition on brass and copper substrates. The sliding distance and the speed of the alloy steel ball used during the sliding wear operation are found to be 3 mm and 4 mm/s, respectively. The sliding wear modelling and simulation process are, however, designed for the ball-on-flat (BoF) wear technique with a dry sliding approach. Therefore, BoF wear simulations are also performed on titanium carbide–brass (TiC-Br) and titanium carbide–copper (TiC-Cu) conjugates for the evaluation of surface engineering applications such as cutting tools and in automotive, aerospace, thermomechanical, and biomedical fields. The ball used for the FEA wear simulation is made from alloy steel material (AISI 52100) with a radius of 3.175 mm. [ABSTRACT FROM AUTHOR]

The calculation of the activation energy helps to understand and to identify the underlying phenomenon of oxidation. We propose a new method without any a priori hypothesis on the oxidation law, to retrieve the activation energy of partially and totally oxidized samples subject to successive annealing. The method handles the uncertainties on the measurement of metal and oxide thicknesses, at the beginning and at the end of the annealing process. The possible change in oxidation law during annealing is included in the model. By using an adapted Particle Swarm Optimization method to solve the inverse problem, we also calculate the time of final oxidation during the last annealing. We apply the method to successive annealings of three samples with initial nanometric layers of copper, at ambient pressure, in the open air. One, two and three successive laws are recovered from experimental data. We found activation energy values about 105–108 kJ mol−1 at the beginning of the oxidation, 76–87 kJ mol−1 at the second step, and finally 47–59 kJ mol−1 in a third step. We also show that the time evolution of copper and oxide thicknesses can also be retrieved with their uncertainties.

In this Letter, we investigate the mechanical stability of HEA-based multilayers after Xe-ion irradiation. CrFeCoNi/TiNbZrTa metallic and nitride thin films with a bilayer thickness of 30 nm were grown by reactive dc-magnetron sputtering on Al2O3(0001) substrates for irradiation studies and on Si(100) substrates for other characterizations. The films were subjected to 3-MeV Xe-ion irradiation at room temperature (RT) and at 500 °C. The crystal structure and mechanical properties of the films before and after irradiation were studied by x-ray diffraction and nanoindentation. Before irradiation, both the metallic and nitride multilayers displayed a lower hardness (7 and 20 GPa, respectively). Annealing at 500 °C for 150 min increased the hardness of the multilayer samples, but it also induced intermixing of elements between the sublayers of the metallic multilayer. Irradiation hardening was observed only in the metallic multilayer at room temperature. When comparing the effects of irradiation damage vs the effects of annealing on the mechanical properties, it was observed that annealing the multilayers had a more pronounced effect. [ABSTRACT FROM AUTHOR]

The efficient conversion of solar energy to heat is a prime challenge for solar thermal absorbers, and various material classes and device concepts are discussed. One exciting class of solar thermal absorbers are plasmonic broadband absorbers that rely on light absorption thanks to plasmonic resonances sustained in metallic nanoparticles. This work focuses on Cu/Al2O3 plasmonic absorbers, which consist of a thin film stack of a metallic Cu‐mirror, a dielectric Al2O3 spacer, and an Al2O3/Cu‐nanoparticle nanocomposite. This work explores two preparation routes for the Al2O3/Cu‐nanoparticle nanocomposite, which rely on the self‐organization of Cu nanoparticles from sputtered atoms, either in the gas phase (i.e., via gas aggregation source) or on the thin film surface (i.e., via simultaneous co‐sputtering). While in either case, Cu‐Al2O3‐Al2O3/Cu absorbers with a low reflectivity over a broad wavelength regime are obtained, the simultaneous co‐sputtering approach enabled better control over the film roughness and showed excellent agreement with dedicated simulations of the optical properties of the plasmonic absorber using a multi‐scale modeling approach. Upon variation of the thickness and filling factor of the Al2O3/Cu nanocomposite layer, the optical properties of the plasmonic absorbers are tailored, reaching an integrated reflectance down to 0.17 (from 250 to 1600 nm). [ABSTRACT FROM AUTHOR]

The thermoreflectance technique is one of the few methods which can measure thermal diffusivity of thin films as thin as 100 nm or thinner in the cross-plane direction. The thermoreflectance method under rear-heat front-detect configuration is sometimes called ultrafast laser flash method because of its similarity to laser flash method. Up to now it has typically only been possible to attempt to evaluate the interfacial thermal resistance between the thin films by preparing and measuring several samples with different thicknesses. In this study, a method to directly determine interfacial thermal resistance by a single measurement of a thin film on substrate is represented, by analyzing the shape of thermoreflectance signals with analytical solutions in frequency domain and time domain. Thermoreflectance signals observed from metallic thin films on sapphire substrate with different thickness steps were analyzed by Fourier analysis and fitted by analytical equations with four parameters: heat diffusion time across the first layer, ratio of virtual heat sources, characteristic time of cooling determined by interfacial thermal resistance and relative amplitude of the signal. Interface thermal resistance between the thin film and substrate was able to be determined reliably with smaller uncertainty. [ABSTRACT FROM AUTHOR]

This study introduces a novel approach for fabricating ZnS/Al2O3/TaSe2 heterostructured core/shell nanowires (NWs) through the selenization of a metallic Ta thin film precursor. The synthesis process involves a meticulously designed four-step protocol: (1) generating ZnS NWs on an oxidized silicon substrate, (2) encapsulating these NWs with a precisely controlled thin Al2O3 layer via atomic layer deposition (ALD), (3) applying a Ta precursor layer by magnetron sputtering, and (4) annealing in a Se-rich environment in a vacuum-sealed quartz ampoule to transform the Ta layer into TaSe2, resulting in the final core/shell structure. The characterization of the newly produced NWs using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) was validated using the integrity and composition of the heterostructures. Our method not only establishes a new pathway for the synthesis of TaSe2-based core/shell NWs but also extends the potential for creating a variety of core/shell NW systems with chalcogenide shells by adapting the thin film metal precursor approach. This versatility opens the way for future advancements in nanoscale material applications, particularly in electronics and optoelectronics where core/shell geometries are increasingly important. [ABSTRACT FROM AUTHOR]

Preparation of a thin organic film on metallic electrodes can protect substrates against corrosion. These organic underlayers also help electrodeposition of metallic electrocatalysts as well as enhance the quality and performance of electrodes. In this study, a thin self-assembled monolayer film of Bingöl pollen (BP-SAM) was fabricated on a copper substrate (Cu/BP-SAM) in pure water as solvent. The film was prepared by exposing a Cu substrate to a 1000 ppm aqueous pollen solution for 24 h assembly time. Then, a small amount of Ni, known for its good catalytic properties for water splitting process, was electrodeposited over the previously assembled SAM film (Cu/BP-SAM/Ni) to enhance its catalytic effect for hydrogen evolution reaction. The modified surfaces were analyzed by scanning electron microscopy (SEM), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDX), and contact angle (CA) studies. Water splitting activity of the Cu/BP-SAM and Cu/BP-SAM/Ni electrodes were investigated in 6 M KOH solution at 298 K. The data obtained indicated that the modification of Cu surface with BP-SAM and BP-SAM/Ni reduces polarization resistance (R p) by 35.3% and 84.4%, respectively at −100 mV cathodic overpotential. The BP-SAM films were adherent to the Cu substracte and have a uniform structure. Ni particles were homogenously deposed over the SAM film and have high quality. The Cu/BP-SAM/Ni electrode has promising electrochemical time-stability during the electrolysis and losses only 6.5% of its activity during the long-time electrolysis. [Display omitted] • A homogeneous and adherent pollen self-assembled monolayer film was assembled on copper. • A small amount of Ni was electrochemically and homogenously deposited on the organic film. • The metal-organic coating exhibits a promising water splitting activity and stability. • The Ni-modified pollen film improves hydrogen evolution performance of electrode by 84.4%. • The Cu/BP-SAM/Ni electrode losses only 6.5% of its activity during electrolysis. [ABSTRACT FROM AUTHOR]

Recently, there has been an increasing interest in optical applications of nanostructured metal thin films based on transparent conductive layers. There is little data published on the study of the optical behavior of ferromagnetic materials such as Co:Fe alloy thin films. DC sputtering technique was used to grow the magnetic crystalline Co:Fe thin films, on glass substrates, in different nano-thicknesses in range of 20, 35, 50, 75 and 100 nm. XRD technique, atomic force microscopy (AFM), and a spectrophotometer of Ultraviolet–visible (UV–Vis) were used to analyze the films. The XRD data confirmed that the samples of Co:Fe films showed out-of-plane direction of 〈 1 1 0 〉. The data indicates that an increase in the average grain size and lattice constant of the films is presented related to increase in the nano-thickness of Co:Fe alloy thin films samples. From AFM, it is illustrated that the roughness of the film is about (Ra = 1. 5 5 7 nm) which is due to the produced grains. The optical response, optical conductivity and electrical conductivity have been affected by the changed nano-thickness of the metallic Co:Fe thin films. [ABSTRACT FROM AUTHOR]

The formation of nanostructures from a thin Au film deposited on a polystyrene and polymethylmethacrylate substrate under keV monatomic P, Ta and molecular PF4 ion irradiation is studied. The formation of nanoparticles on both kinds of polymers is shown. Heavy Ta ions are most effective in altering the Au layer, whereas its transformation by light P or molecular PF4 ions is less pronounced. Irradiation with PF4 ions has a much smaller effect on the PS and PMMA substrate bulk compared to that with monatomic P ions. The crucial role of collision cascade density in the process of thin metallic film coagulation on polymer substrate is revealed. During ion bombardment, transmitted IR light intensity increases proportionally to the area covered by the metal film, which makes it possible to use FTIR as a rapid technique to estimate the state of the nanoparticle formation process. [ABSTRACT FROM AUTHOR]

In order to assess the longevity of foldable electronics, folding or bending tests on model systems need to be performed. However, not all bending tests are created equal in that different configurations lead to different amounts of mechanical damage and thus different electrical responses. Two 90° bending instruments were compared using two model metallic thin film systems on polyimide to establish if the two seemingly similar bending tests yield the same results. The two film systems, namely 300 nm Mo and 130 nm Al on 50 nm Mo, were magnetron-sputtered on polyimide substrates and tested in the custom-built FLEX-E-TEST and the commercially available YUASA test that is capable of in situ resistance measurements. For statistics, 10–12 samples were tested of each film system on each folding device using the same applied bending strain and number of cycles. Samples were intermittently characterized with confocal laser scanning microscopy and electrical resistance to correlate the amount of mechanical damage (crack density) with the electrical normalized resistance ratio of the damaged area. The results show that even with the same bending radius, a similar but not identical amount of mechanical damage forms for both bending devices. Additionally, the resistance as a function of cycles also differs after 10,000 cycles. A closer examination of the damage, especially in the Al/Mo film system, indicates that the speed of the bending, and if the samples experience spring back, can alter the received mechanical damage. The in situ resistance data of the YUASA test were further examined and a suggestion of standardizing how folding or bending test results are reported is provided. [ABSTRACT FROM AUTHOR]

Metallic nanoshells have emerged as promising optical cavities to steer hybridized plasmonic resonances that show the high spectral tunability and a large surface area of localized fields. Despite various optical and photochemical applications, plasmonic resonances in shells have rarely been explored at low frequencies due to a nonlinear increase in particle size and a rapid degeneration in field localization. Here, this work reports the experimental realization of hybridized plasmon resonances in origami metashells that can be excited by low‐energy photons ≈7 GHz, corresponding to a level below 10−4 eV. Metasurfaces built of interconnected meshes act as thin Drude metallic films that support symmetric spoof surface plasmons. Rigid folding of the metasurface leads to diverse 3D hollow cavities that exhibit strong plasmonic responses, large surface areas, and low relative densities. Experimental measurements demonstrate three typical behaviors in Drude metallic shells: shielding to quasi‐static fields, strong scattering at first‐order hybridized plasmon resonances, and transparency to high frequency radiation. The relative density is remarkably reduced owing to the void cavity enabled by 3D folding, and an extra degree of freedom in anisotropic load capacity is provided by customizing crease patterns. These results open a door for extremely low‐energy plasmons with low‐density mechanics. [ABSTRACT FROM AUTHOR]

Microelectromechanical systems (MEMS)-based capacitive pressure sensors are conventionally fabricated from diaphragms made of Si, which has a high elastic modulus that limits the control of internal stress and constrains size reduction and low-pressure measurements. Ru-based thin-film metallic glass (TFMG) exhibits a low elastic modulus, and the internal stress can be controlled by heat treatment, so it may be a suitable diaphragm material for facilitating size reduction of the sensor without performance degradation. In this study, a Ru-based TFMG was used to realize a flattened diaphragm, and structural relaxation was achieved through annealing at 310 °C for 1 h in a vacuum. The diaphragm easily deformed, even under low differential pressure, when reduced in size. A diaphragm with a diameter of 1.7 mm was then applied to successfully fabricate a capacitive pressure sensor with a sensor size of 2.4 mm2. The sensor exhibited a linearity of ±3.70% full scale and a sensitivity of 0.09 fF/Pa in the differential pressure range of 0–500 Pa. [ABSTRACT FROM AUTHOR]

This work presents a new ultra-high vacuum cluster tool to perform systematic studies of the early growth stages of atomic layer deposited (ALD) ultrathin films following a surface science approach. By combining operando (spectroscopic ellipsometry and quadrupole mass spectrometry) and in situ (X-ray photoelectron spectroscopy) characterization techniques, the cluster allows us to follow the evolution of substrate, film, and reaction intermediates as a function of the total number of ALD cycles, as well as perform a constant diagnosis and evaluation of the ALD process, detecting possible malfunctions that could affect the growth, reproducibility, and conclusions derived from data analysis. The homemade ALD reactor allows the use of multiple precursors and oxidants and its operation under pump and flow-type modes. To illustrate our experimental approach, we revisit the well-known thermal ALD growth of Al2O3 using trimethylaluminum and water. We deeply discuss the role of the metallic Ti thin film substrate at room temperature and 200 °C, highlighting the differences between the heterodeposition (<10 cycles) and the homodeposition (>10 cycles) growth regimes at both conditions. This surface science approach will benefit our understanding of the ALD process, paving the way toward more efficient and controllable manufacturing processes. [ABSTRACT FROM AUTHOR]

When a laser beam writes on a metallic film, it usually coarsens and deuniformizes grains because of Ostwald ripening, similar to the case of annealing. Here we show an anomalous refinement effect of metal grains: A metallic silver film with large grains melts and breaks into uniform, close-packed, and ultrafine (∼ 10 nm) grains by laser direct writing with a nanoscale laser spot size and nanosecond pulse that causes localized heating and adaptive shock-cooling. This method exhibits high controllability in both grain size and uniformity, which lies in a linear relationship between the film thickness (h) and grain size (D), D ∝ h. The linear relationship is significantly different from the classical spinodal dewetting theory obeying a nonlinear relationship (D ∝ h5/3) in common laser heating. We also demonstrate the application of such a silver film with a grain size of ∼ 10.9 nm as a surface-enhanced Raman scattering chip, exhibiting superhigh spatial-uniformity and low detection limit down to 10−15 M. This anomalous refinement effect is general and can be extended to many other metallic films. [ABSTRACT FROM AUTHOR]

Abstract In this study, a surface plasmon resonance sensor for detecting haemoglobin concentration based on a D‐type optical fibre with a graphene‐gold surface architecture is proposed. The graphene‐gold surface architecture included a 50 nm thick gold film and monolayer graphene film, which were decorated on a 10 mm long D‐type sensing region. The proposed sensor worked in wavelength interrogation mode, with the light wavelength ranging from 400 to 1100 nm. The authors realised the D‐type optical fibre surface polishing process, the gold film vacuum coating process, and the chemical‐vapour‐deposited graphene's wet transfer process. Furthermore, the fabricated sensors were used to detect the refractive index (RI) of haemoglobin samples, which varied from 1.331 to 1.346. Experiment results show that the fitted RI sensitivity of the sensor decorated with gold and graphene reaches 1874.41 nm/RIU, 4.995% higher than that of the sensor decorated only with gold. The concentration sensitivity of the sensor coated with gold and graphene film is 4.96 nm/(g/dL), and the proposed sensor can provide a resolution of 20.2 mg/dL for haemoglobin concentration detection.

Itinerant kagome lattice magnets exhibit many novel correlated and topological quantum electronic states with broken time-reversal symmetry. Superconductivity, however, has not been observed in this class of materials, presenting a roadblock in a promising path toward topological superconductivity. Here, we report that novel superconductivity can emerge at the interface of kagome Chern magnet TbMn6Sn6 and metal heterostructures when elemental metallic thin films are deposited on either the top (001) surface or the side surfaces. Superconductivity is also successfully induced and systematically studied by using various types of metallic tips on different TbMn6Sn6 surfaces in point-contact measurements. The anisotropy of the superconducting upper critical field suggests that the emergent superconductivity is quasi-two-dimensional. Remarkably, the interface superconductor couples to the magnetic order of the kagome metal and exhibits a hysteretic magnetoresistance in the superconducting states. Taking into account the spin-orbit coupling, the observed interface superconductivity can be a surprising and more realistic realization of the p-wave topological superconductors theoretically proposed for two-dimensional semiconductors proximity-coupled to s-wave superconductors and insulating ferromagnets. Our findings of robust superconductivity in topological-Chern-magnet/metal heterostructures offer a new direction for investigating spin-triplet pairing and topological superconductivity. The authors deposit non-superconducting metallic thin films on surfaces of the kagome Chern magnet TbMn6Sn6 and observe emergent superconductivity even though neither component is a superconductor. Furthermore, the superconducting state is quasi-two-dimensional and coexists with ferromagnetism, consistent with possible spin-triplet pairing and topological superconductivity. [ABSTRACT FROM AUTHOR]

Perfect absorbers have received significant attention due to their tunable and extraordinary absorptive behaviour of light at selected wavelengths. Such absorption can be achieved by means of nanostructured materials with various types of flexibility. Despite these advantages, nanofabrication is a challenging process. In this study, we manufacture and characterize a gold thin-film-based ultra narrow-band perfect absorber that does not require nanostructures for full absorption of the incident light. Perfect absorption is based on Fabry-Perot interference created using a metal-insulator-metal triple layer. The fabrication involves precise deposition of a gold film (35 nm) and silicon nitride dielectric film (110-170 nm) in a controlled fashion. Optical characterization is achieved using a portable, simple reflection probe. The fabricated multi-layer thin film demonstrates ultra-narrow bandwidth (25 nm) and 99.4% maximum absorption. The use of gold thin film ensures inertness and makes the proposed system robust under harsh environmental conditions, unlike other metals. Our findings underscore the potential of this engineered perfect absorber for applications in photovoltaics and as optical filters; but not in sensing. We show that the electric field is bound between the metallic thin films and not affected by the change of refractive index outside the system. [ABSTRACT FROM AUTHOR]

The existing color filter implementation schemes are prone to introduce prestress during the preparation process due to the large difference in thermal expansion coefficients of different layers of materials, resulting in poor mechanical stability. Inspired by beetle forewings' structure, it is proposed to construct asymmetric Fabry–Perot (F‐P) angular heterochromatic structural colors utilizing homologous materials through a continuous deposition method of magnetron sputtering technology. The fabricated large‐area F‐P‐type reflective filters not only exhibit high color saturation but also achieve good bonding ability between the layers with a steady‐state friction coefficient of ≈0.1. The large‐area reflective filter can achieve different colors such as blue, yellow, violet, and green, which is in agreement with the simulation results. This work not only provides a new design method for advanced decorative applications but also provides protection to the substrate. [ABSTRACT FROM AUTHOR]

Zirconium-based metallic glass films are promising materials for nanoelectronic and biomedical applications, but their mechanical behavior under different conditions is not well understood. This study investigates the effects of radio frequency (RF) power and test temperature on the nanostructure, morphology, and creep behavior of Zr55Cu30Al10Ni5 metallic glass films prepared by RF magnetron sputtering. The films were characterized by X-ray diffraction and microscopy, and their mechanical properties were measured by a bulge test system. The results show that the films were amorphous and exhibited a transition from noncolumnar to columnar morphology as the RF power increased from 75 W to 125 W. The columnar morphology reduced the creep resistance, Young's modulus, residual stress, and hardness of the films. The creep behavior of the films was also influenced by the test temperature, with higher temperature leading to higher creep strain and lower creep stress. The findings of this study provide insights into the optimization of the sputtering parameters and the design of zirconium-based metallic glass films for various applications. [ABSTRACT FROM AUTHOR]

This paper presents an alternative optical characterization of biosensors based on supported lipid monolayers (SLMs). Developing these biosensors requires precise thickness characterization of the films to understand their structure and dynamics. This paper proposes an optical technique to measure the thickness, optical properties, and location of a dipalmitoyl-phosphatidylcholine (DPPC) SLM on top of a metallic thin film. DPPC SLMs are of interest for biosensing applications, such as detecting pulmonary-related infections like SARS-CoV-2, Avian Influenza, and the H1N1 influenza virus. The monolayer was fabricated using the Langmuir–Blodgett technique, and the experimental characterization consisted of measuring the surface-plasmon resonance angle in the Kretschmann configuration. This technique provides an alternative option for real-time visual inspection and determination of the location and shape of DPPC monolayers in large areas. Therefore, it offers a useful tool for further developing SLM-based biosensors. [ABSTRACT FROM AUTHOR]

In this study, a surface plasmon resonance sensor for detecting haemoglobin concentration based on a D‐type optical fibre with a graphene‐gold surface architecture is proposed. The graphene‐gold surface architecture included a 50 nm thick gold film and monolayer graphene film, which were decorated on a 10 mm long D‐type sensing region. The proposed sensor worked in wavelength interrogation mode, with the light wavelength ranging from 400 to 1100 nm. The authors realised the D‐type optical fibre surface polishing process, the gold film vacuum coating process, and the chemical‐vapour‐deposited graphene's wet transfer process. Furthermore, the fabricated sensors were used to detect the refractive index (RI) of haemoglobin samples, which varied from 1.331 to 1.346. Experiment results show that the fitted RI sensitivity of the sensor decorated with gold and graphene reaches 1874.41 nm/RIU, 4.995% higher than that of the sensor decorated only with gold. The concentration sensitivity of the sensor coated with gold and graphene film is 4.96 nm/(g/dL), and the proposed sensor can provide a resolution of 20.2 mg/dL for haemoglobin concentration detection. [ABSTRACT FROM AUTHOR]

Hafnium dioxide (HfO2)-based ferroelectric films are highly desirable due to their excellent compatibility with CMOS technology, good scalability, low operating voltage, and moderate polarization strength. However, the preparation of HfO2-based ferroelectric films inevitably introduces oxygen vacancies, which, under the influence of electric fields, redistribute and cause the awakening and fatigue phenomena of the films, ultimately resulting in the loss of ferroelectric performance. In this study, Hf0.5Zr0.5O2 (HZO) thin films were grown using atomic layer deposition (ALD) technology, and the influence of using different metal electrodes (W, Pt) as the top and bottom electrodes on the electrical properties of the HZO films was investigated. The leakage current of the W/HZO/W capacitor was the lowest, and the initial 2Pr at 3 V was 41.4 μC/cm2, much higher than those of the W/HZO/Pt (15.7 μC/cm2) and Pt/HZO/Pt (7.6 μC/cm2) capacitors. As the number of electric field cycles gradually increased to 104, the 2Pr values of the three capacitors changed. At this point, the 2Pr value of the W/HZO/W capacitor was 53.9 μC/cm2, and the characteristic fatigue curve was flatter, indicating a weaker wake-up effect. These results indicate that the W electrode material can effectively promote the formation of the ferroelectric phase, reduce oxygen vacancies, and suppress the wake-up effect. [ABSTRACT FROM AUTHOR]

Ti1-xHoxO2 (x= 0.0, 0.01, 0.02, 0.03) thin films are synthesized by a sol-gel method and deposited by a dip-coating technique on the glass substrates. The films' crystal structures are examined by an X-ray diffraction technique, while the morphological properties are investigated by scanning electron microscopy and atomic force microscopy. UV-Vis and photoluminescence spectrophotometry are used to analyze the optical properties. Based on the X-ray diffraction patterns, all the films belong to the anatase phase. It is observed that the surface characteristics, such as the morphology, film thickness, and roughness change significantly with the holmium substitution. The optical investigations reveal that the transmittance, band gap energies, and luminescence properties can be adjusted by the holmium substitution. According to the current study, holmium substituted TiO2 thin films with improved optical properties may be a suitable candidate for applications that require a wide band gap and high optical transparency as well as luminescence properties. [ABSTRACT FROM AUTHOR]

In this work, 80-nm Bi3.15Nd0.85Ti3O12 thin films with different annealing temperature have been successfully fabricated on p-type silicon substrates by sol-gel method. The effect of annealing temperature on the microstructure, dielectric properties, and energy-storage performances of the thin films were investigated in detail. The prepared films at 750 °C had a layered perovskite structure with an excellent crystalline morphology, featuring a high dielectric constant of 43.8 and a low dielectric loss < 2% at 1 kHz, which lead the significantly improvement of breakdown strength to increase the energy storage properties. The maximum recoverable energy density of 4.3 J/cm3 with an efficiency of 70.7% under the electric field of 1.90 MV/cm has been obtained for the Bi3.15Nd0.85Ti3O12 film capacitors at 750 °C. These properties indicate that Bi3.15Nd0.85Ti3O12 system is a promising environmentally friendly lead-free ferroelectric. [ABSTRACT FROM AUTHOR]

Free-electron lasers provide bright, ultrashort, and monochromatic x-ray pulses, enabling novel spectroscopic measurements not only with femtosecond temporal resolution: The high fluence of their x-ray pulses can also easily enter the regime of the non-linear x-ray–matter interaction. Entering this regime necessitates a rigorous analysis and reliable prediction of the relevant non-linear processes for future experiment designs. Here, we show non-linear changes in the L 3 -edge absorption of metallic nickel thin films, measured with fluences up to 60 J/cm2. We present a simple but predictive rate model that quantitatively describes spectral changes based on the evolution of electronic populations within the pulse duration. Despite its simplicity, the model reaches good agreement with experimental results over more than three orders of magnitude in fluence, while providing a straightforward understanding of the interplay of physical processes driving the non-linear changes. Our findings provide important insights for the design and evaluation of future high-fluence free-electron laser experiments and contribute to the understanding of non-linear electron dynamics in x-ray absorption processes in solids at the femtosecond timescale. [ABSTRACT FROM AUTHOR]

Some mechanisms of creep, especially those involving dislocations for many crystalline materials, can be verified by direct microstructural examination. However, metallic glass thin films (MGTFs) are disordered materials lacking the long-range order of crystals. Even today, the creep mechanisms for amorphous alloys are far from being fully understood. The physical factors governing localization and instability during creep deformation are still elusive. In this work, Ni60Nb40 alloys with high kinetic stability were prepared by magnetron sputtering at different substrate temperatures to obtain MGTFs with different internal states. We report a close correlation between the internal states and the creep resistance of the MGTFs and reveal that altering the substrate temperature during magnetron sputtering can induce changes in the surface morphologies, plastic deformation resistance, and creep resistance of Ni60Nb40 MGTFs. The creep deformation mechanism is interpreted based on the shear transformation zone (STZ) model of amorphous alloys, and our results may have implications for understanding the role of STZs during creep deformation of MGTFs. [ABSTRACT FROM AUTHOR]

The growth, sintering, and interaction of cobalt with ceria were studied under ultrahigh vacuum conditions by vapor-deposition of Co onto well-defined CeOx(111) (1.5 < x < 2) thin films grown on Ru(0001). Charge transfer from Co to ceria occurs upon deposition of Co on CeO1.96 and partially reduced CeO1.83 at 300 K. X-ray photoelectron spectroscopy studies show that Co is oxidized to Co2+ species at the cost of the reduction of Ce4+ to Ce3+, at a lesser extent on reduced ceria. Co2+ is the predominant species on CeO1.96 at low Co coverages (e.g., ≤0.20 ML). The ratio of metallic Co/Co2+ increases with the increase in the Co coverage. However, both metallic Co and Co2+ species are present on CeO1.83 even at low Co coverages with metallic Co as the major species. Scanning tunneling microscopy results demonstrate that Co tends to wet the CeO1.96 surface at very low Co coverages at room temperature forming one-atomic layer high structures of Co–O–Ce. The increase in the Co coverage can cause the particle growth into three-dimensional structures. The formation of slightly flatter Co particles was observed on reduced CeO1.83. In comparison with other transition metals including Ni, Rh, Pt, and Au, our studies demonstrate that Co on ceria exhibits a smaller particle size and higher thermal stability, likely arising from strong metal–support interactions. The formed particles upon Co deposition at 300 K are present on the ceria surface after heating to 1000 K. The Co–ceria interface can be tuned by varying the Co metal coverage, the annealing temperature, and the nature of the ceria surface. [ABSTRACT FROM AUTHOR]

In this work, we report nearly single oriented {001}-textured ferroelectric PbZr 0.52 Ti 0.48 O 3 thin films grown by pulsed laser deposition onto AISI 304 stainless steel substrates. Pt, Al 2 O 3 , and LaNiO 3 buffer layers promote the PbZr 0.52 Ti 0.48 O 3 {001} texture and protect the substrate against oxidation during deposition. The dominant {001} texture of the PbZr 0.52 Ti 0.48 O 3 layer was confirmed using x-ray and electron backscatter diffraction. Before poling, the films exhibit a permittivity of about 350 at 1 kHz and a dielectric loss below 5%. The films display a remanent polarization of about 16.5 μ C cm − 2 and a high coercive field of up to E c = 135.9 kV cm − 1 . The properties of these PbZr 0.52 Ti 0.48 O 3 thin films on stainless steel are promising for various MEMS applications such as transducers or energy harvesters. [ABSTRACT FROM AUTHOR]

Silicon pore optics are a new type of high-performance x-ray optics designed to enable future space-borne x-ray observatories such as European Space Agency's Athena. These optics will make it possible to build telescopes with effective areas of the order of a few square meters and angular resolutions better than 5 s of arc. During manufacturing of the optics, thin film metallic coatings are sputtered onto mirror plates to help achieve this large effective area. Then, these plates are stacked on top of each other using direct silicon bonding to achieve the shape of an approximate Wolter type-I telescope design. It is, therefore, necessary to verify the compatibility of the coating and bonding processes. We observe the unintentional removal of coatings on silicon pore optics plates after their wet chemical activation, a step required to make direct bonding possible. In this paper, we investigate plasma etching prior to thin film deposition as a solution to this problem. First, we ensure that plasma etching does not impact the low surface roughness required to achieve high imaging performance. Then, we demonstrate that plasma etching before thin film deposition prevents unintentional removal of the metallic coatings during the activation step, making coating deposition compatible with direct bonding of silicon pore optics plates. [ABSTRACT FROM AUTHOR]