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Development of L10-ordered FePt with low damping and large perpendicular magnetic anisotropy by engineering the nanostructure
THz spintronics is an emergent area of research aimed at bridging the gap between fifth- and sixth-generation wireless telecommunications by utilizing spintronic devices such as magnetic spin torque oscillators as a source of low powered THz emission. The realization of such devices using ferromagnetic metal thin films however requires magnetic materials with both large perpendicular magnetic anisotropy (PMA) and low Gilbert damping constants. In this Letter, we report on the development of L10-ordered FePt with an effective Gilbert damping constant as low as 0.033. Using time-resolved magneto-optical Kerr effect, we characterized the magnetization dynamics of continuous L10-ordered FePt grown on MgO and SrTiO3 substrates. By changing the substrate on which FePt is grown, the lattice mismatch and subsequent number of misfit dislocations at the interface and L10-ordering can be controlled. We found that fewer misfits and improved ordering in FePt lead to a reduced Gilbert damping constant due to reduced electron scattering but that FePt grown on SrTiO3 also shows robust perpendicular magnetic anisotropy. Importantly, these results demonstrate the ability to control the damping in FePt and similar materials by changing the number of misfit dislocations at the interface and the smaller damping in FePt opens up the possibility of using this material in spintronic materials in the THz wave range.
A pilot study comparing three-dimensional models of tumor histopathology and magnetic resonance imaging
<i>P</i>-type surface charge transfer doping of diamond via low-dimensional transition metal oxides
Device applications of ultra-wide-bandgap diamond rely on the precise control of both carrier type and concentration. However, due to the strong covalent bonds in bulk diamond, conventional doping methods have struggled to achieve large-scale tuning of its properties. Surface charge transfer doping (SCTD) is seen as a simple and effective solution, leveraging energy-level differences between surface dopant and the semiconductor to regulate carrier properties efficiently. Here, we conducted a comprehensive theoretical study on p-type SCTD of hydrogen-terminated diamond (100) surface [diamond(100):H] using low-dimensional transition metal oxides. The doping effects of the molecular MoO3 and monolayer MoO3 were first explored. The areal hole density for molecular-MoO3-doped diamond(100):H sharply rises and then slightly decreases with increasing MoO3 density, reaching a peak of 7.55 × 1013 cm−2—surpassing the maximum value achieved with a MoO3 monolayer. For identical MoO3 densities, a stronger interaction with diamond(100):H results in a greater areal hole density. We also studied one-dimensional chain-like CrO3 and two-dimensional layered V2O5. However, a V2O5 monolayer cannot achieve the saturation areal hole density due to the large energy separation between the conduction band minimum (CBM) of V2O5 and the valence band maximum (VBM) of diamond(100):H. Increasing the number of V2O5 monolayers will enhance the doping effect. Overall, optimal doping can be achieved with smaller dimensions, higher density and thickness of the transition metal oxides, stronger interactions with diamond(100):H, and a larger energy separation between the dopant's CBM and diamond(100):H's VBM. This study provides theoretical guidance to develop superior diamond-based electronic and optoelectronic devices.
Production scheduling with multi-robot task allocation in a real industry 4.0 setting
Topology of far-field signals for photonic crystal slabs
The study of band topology in photonic crystals was primarily focused on near-field effects, including edge states and high-order corner states. However, this work investigated the polarization distribution of radiated fields for photonic crystal slabs to get their far-field properties of band topology. We introduced a topological invariant—the winding number of far-field polarization around the Brillouin zone boundary and confirmed a robust correspondence between it and the Chern number of energy bands from the perspective of symmetry, which can be used to analyze the process of topological phase transition. It is found that changes in the winding number and Chern number, associated with the exchange of far-field polarization singularities, especially for bound states in the continuum, will emerge during phase transition. These findings offer insights for further understanding the intriguing properties of topological materials.
Exploring the influence of age on the causes of death in advanced nasopharyngeal carcinoma patients undergoing chemoradiotherapy using machine learning methods
Nonreciprocal and nonlinear transport and spontaneous voltage generation in MoGe/Ni81Fe19
The nonreciprocal, diode-like electric transport in a superconductor/ferromagnet bilayer system, MoGe/Ni81Fe19, has been investigated. We found that a MoGe film on Ni81Fe19 spontaneously generates d.c. voltage by rectifying environmental fluctuations. By comparing the effect between MoGe films on different magnetic materials, we show that the amplitude of the spontaneous voltage generation is almost proportional to that of the nonreciprocal electric transport in MoGe, suggesting that the observed rectification mainly originates from the motion of superconducting vortex strings that can feel asymmetry in the magnetic environment between the MoGe surfaces.
Enhancing proteasome activity by NMDAR antagonists explains their therapeutic effect in neurodegenerative and mental diseases
High AC field-induced polarization switching unraveled in frequency domain: Enhanced dielectric responses in lanthanum-doped Pb(Ni1/3Nb2/3)O3-Pb(Zr,Ti)O3 relaxor-ferroelectrics
In this study, we delve into the complex dielectric behaviors of lanthanum (La)-doped PNN-PZT relaxor-ferroelectric ceramics under the influence of high AC fields. Our approach involves a meticulous design of dielectric measurements to scrutinize the decoupling phenomenon between local polarization oscillation and global polarization switching. Remarkably, the application of high AC fields (&gt;0.5 kV/mm) causes a dramatic increase in the dielectric permittivity (2x), alongside pronounced frequency dispersion (&gt;65 °C) and a permittivity hump below Tm in 7% La-doped relaxor compositions. For relaxor-ferroelectric ceramics doped with lower La (&lt;=5%) that are featured with tweed-like submicron domains as imaged in in situ transmission electron microscopy, the significantly enhanced dielectric permittivity and dielectric loss (&gt;1) are induced under high AC fields (&lt;0.5 kV/mm). A comparative study with a polarization loop in the time domain under various AC fields and DC bias demonstrates that the dielectric anomaly in the frequency domain is associated with global polarization switching, co-existing with polarization oscillation mechanism in various domains. This frequency domain method reveals threshold AC fields (0.25–0.5 kV/mm) above which polarization switching occurs in relaxor-FE compositions at elevated temperatures, complements the dynamic behaviors of P–E hysteresis, and cautions the control of AC fields in dealing with relaxor-ferroelectric materials for advanced electronic applications.
Water hyacinth conversion to biochar for soil nutrient enhancement in improving agricultural product
Enhancing charge carrier dynamics with an N-type polymer guest for printable ternary organic solar modules
The ternary strategy offers a promising route to enhance the power conversion efficiencies (PCEs) of organic solar cells (OSCs). In this contribution, we focus on the state-of-the-art binary system PM6:L8-BO and reveal how the n-type polymer guest (PYIT) in the PM6:L8-BO:PYIT ternary system enhances carrier dynamics, thereby improving both efficiency and scalability for large-area printable OSC modules. These benefits are primarily attributed to two key factors: (i) the excellent miscibility of the PYIT guest with the host materials, coupled with the chain-dominant structure and high crystallinity nature of the PYIT polymer, which creates additional pathways for carrier transport and charge transfer; (ii) the incorporation of PYIT, which limits the excessive aggregation of L8-BO, improves molecular packing, and reduces film defects, thereby enhancing exciton dynamics. These optimizations lead to an increase in PCEs from 17.58% in the binary system to 18.59% in the ternary OSC, with improvements across all photovoltaic parameters. More importantly, the PM6:L8-BO:PYIT ternary system exhibits excellent compatibility with large-area printing processes, as demonstrated by a doctor blading OSC module achieving 15.57% PCE over an area of 11.7 cm2. This work highlights the potential of the ternary methodology in tuning the physical properties of OSCs while enhancing both performance and scalability.
CCN1 promotes APRIL/BAFF signaling in esophageal squamous cell carcinoma but attenuates it in esophageal adenocarcinoma
Special issue APL organic and hybrid photodetectors
Using a citizen science approach to assess nanoplastics pollution in remote high-altitude glaciers
Abstract Nanoplastics are suspected to pollute every environment on Earth, including very remote areas reached via atmospheric transport. We approached the challenge of measuring environmental nanoplastics by combining high-sensitivity TD-PTR-MS (thermal desorption-proton transfer reaction-mass spectrometry) with trained mountaineers sampling high-altitude glaciers (“citizen science”). Particles < 1 μm were analysed for common polymers (polyethylene, polyethylene terephthalate, polypropylene, polyvinyl chloride, polystyrene and tire wear particles), revealing nanoplastic concentrations ranging 2–80 ng mL − 1 at five of 14 sites. The dominant polymer types found in this study were tire wear, polystyrene and polyethylene particles (41%, 28% and 12%, respectively). Lagrangian dispersion modelling was used to reconstruct possible sources of micro- and nanoplastic emissions for those observations, which appear to lie largely to the west of the Alps. France, Spain and Switzerland have the highest contributions to the modelled emissions. The citizen science approach was found to be feasible providing strict quality control measures are in place, and is an effective way to be able to collect data from remote and inaccessible regions across the world.
Sliding ferroelectricity influenced by charge doping in bilayer antiferromagnetic H–ScO2
Sliding ferroelectricity has been extensively studied as it provides an approach to designing van der Waals ferroelectric materials with nonpolar components. In this work, we demonstrate the sliding ferroelectricity of bilayer H–ScO2, which is formed by an interlayer antiferromagnetic configuration of monolayer H–ScO2 ferromagnetic material. The out-of-plane polarization results from charge transfer between the layers, causing an unequal charge distribution within them and yielding a polarization value of ±1.26 pC/m. We found that increasing the doping concentration suppresses the polarization value. This phenomenon results from the differing occupancy ratios of electrons and holes in the conduction and valence bands after introducing electron or hole doping into the system. The closer the number of electrons in the conduction band is to that in the valence band, the more pronounced the suppression of polarization. Our work offers a perspective for the design of advanced van der Waals ferroelectric materials.
Psychometric study of the Maslach Burnout Inventory-Student Survey on Thai university students
Abstract The Maslach Burnout Inventory-Student Survey (MBI-SS) is a widely used instrument to assess burnout levels, which provides valuable insight into their psychological well-being. Accurate measurement of burnout is crucial for developing interventions aimed at reducing stress and promoting mental health among students. This study aims to validate the MBI-SS when applied among Thai university students and to examine whether the psychometric properties of the scale are consistent with the original conceptual framework. A total of 413 undergraduate students from Thailand participated in the study, with 57.63% females and 42.37% males, and a mean age 21.75 years (SD = 2.40). The MBI-SS was translated into Thai by following rigorous procedures to maintain accuracy and cultural relevance. The factorial structure of the MBI-SS Thai version was evaluated using confirmatory factor analysis (CFA) for both a three-factor model and second-order factor model. The Thai version of the MBI-SS demonstrated a three-dimensional structure consistent with the original inventory, with excellent model fit indices. All item factor loadings exceeded the recommended threshold, and the instrument showed high internal consistency, establishing it a valuable tool for future research and practical application in educational settings aimed at addressing and reducing student burnout.
Continuous and spontaneous directional droplet transport on bioinspired serial-wedge-shaped groove with wettability gradient
We propose a serial-wedge-shaped groove with a wettability gradient to achieve continuous directional transport of droplets. Molecular dynamics simulations demonstrate that this design provides a sustained driving force and reduces energy barriers at junctions, facilitating continuous droplet motion. Moreover, higher temperatures and greater wettability gradients are shown to enhance the efficiency of continuous transport. Theoretical analysis further reveals that increasing surface hydrophobicity, width ratio, and droplet size can reduce energy barriers, thereby improving transport performance. These findings are expected to improve the understanding of continuous directional droplet transport and shed light on its manipulation.