Rashba spin-orbit coupling (RSOC) facilitates spin manipulation without relying on an external magnetic field, opening up exciting possibilities for advanced spintronic devices. In this paper, we examine the effects o...
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Rashba spin-orbit coupling (RSOC) facilitates spin manipulation without relying on an external magnetic field, opening up exciting possibilities for advanced spintronic devices. In this paper, we examine the effects of crystal momentum (k) nonlinearity and anisotropy on the conventional Rashba effect, with a particular focus on their impact on the spin Hall conductivity (SHC) in a newly predicted family of 2D Janus materials, W2COX (X=S, Se, Te). Using first-principles density functional theory calculations, we confirm the dynamical and mechanical stability of the studied 2D materials. Strikingly, this materials family exhibits pronounced nonlinear Rashba spin splitting at the Γ point of Brillouin zone near the Fermi level, which cannot be adequately described by the linear-k Rashba model. Therefore, third-order momentum contributions (k3) must be incorporated into the Rashba Hamiltonian. Our analysis reveals that among the studied systems, W2COS exhibits the highest k3 contribution of −45.9 eV Å3, despite having the lowest linear Rashba constant. A detailed analysis of electronic structure reveals topologically nontrivial behavior in these 2D materials, yielding sizable SHC that is primarily governed by the nonlinear Rashba effect. Notably, these materials also exhibit large spin Hall angle (0.018–2.5 at EF), which is comparable to that of in bulk topological insulators like Bi2Se3 and Bi2Te3, and surpassing those in narrow bandgap bulk semiconductors GeTe and SnTe, as well as heavy metals such as Pt. Sizable SHC, large spin Hall angles, and the ability to tune SHC via electric fields without altering the topological properties, rooted in the crystal field splitting, underscore the potential of these materials for spintronic applications.
Liquid junctions in electrochemical cells introduce potentials that can strongly affect measurements. Such liquid-junction potential errors can exceed 100 mV. In the analysis of charge-transfer thermodynamics, error d...
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Background:The convergence of smartphone technology and artificial intelligence(AI)has revolutionized the landscape of ophthalmic care,offering unprecedented opportunities for diagnosis,monitoring,and management of oc...
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Background:The convergence of smartphone technology and artificial intelligence(AI)has revolutionized the landscape of ophthalmic care,offering unprecedented opportunities for diagnosis,monitoring,and management of ocular ***,there is a lack of systematic studies on discussing the integration of smart-phone and AI in this *** text:This review includes 52 studies,and explores the integration of smartphones and AI in ophthalmology,delineating its collective impact on screening methodologies,disease detection,telemedicine initiatives,and patient *** collective findings from the curated studies indicate promising performance of the smartphone-based AI screening for various ocular diseases which encompass major retinal diseases,glaucoma,cataract,visual impairment in children and ocular surface ***,the utilization of smartphone-based imaging modalities,coupled with AI algorithms,is able to provide timely,efficient and cost-effective screening for ocular *** modality can also facilitate patient self-monitoring,remote patient monitoring and enhancing accessibility to eye care services,particularly in underserved *** involving data pri-vacy,algorithm validation,regulatory frameworks and issues of trust are still need to be ***,evaluation on real-world implementation is imperative as well,and real-world prospective studies are currently ***:Smartphone ocular imaging merged with AI enables earlier,precise diagnoses,personalized treat-ments,and enhanced service accessibility in eye *** is crucial to navigate ethical and data security challenges while responsibly leveraging these innovations,promising a potential revolution in care access and global eye health equity.
Antiferromagnet (AFM) has currently participated in the spin-orbit torque (SOT) magnetoresistive random access memory (MRAM) technolopgy due to its great potential to be applied to the field-free SOT switching and pro...
Antiferromagnet (AFM) has currently participated in the spin-orbit torque (SOT) magnetoresistive random access memory (MRAM) technolopgy due to its great potential to be applied to the field-free SOT switching and promote the thermal stability of MRAM. However, effect of the introduction of AFM into the basic structure of SOT-MRAM composed of a heavy metal/ferromagnet (FM) bilayer was still not comprehensively understood. This work reports the effect of how an antiferromagnetic (AFM) order modifies the strength of Dzyaloshinskii-Moriya interaction (DMI) in a heavy metal (Pt)/FM (Co)/AFM (IrMn) trilayer, studied by SOT switching and loop-shift method. Increasing the AFM order reflected on exchange bias (H ex ) through increasing the thickness of IrMn appears to significantly reduce the DMI strength of the trilayer, which leads to the reduction of the external field for yielding a complete SOT switching. The reduced DMI strength may ascribe to the Hex-hosted uni-directional anisotropy suppressing the neighboring spin canting in the FM layer. This stabilization for the magnetic moments via the H ex -hosted uni-directional anisotropy also improved the stability of SOT switching on the random read/write characterization, in which the strong AFM order would promote the memristivity for neuromorphic application and the weak AFM order would give rise to the stochasticity for the purpose of physically unclonable functionality. This work demonstrates the significance of an intrinsic tuning over the AFM order would serve as a switch to turn the SOT device into a stochastic/memristive cell to bridge probabilistic and neuromorphic computing.
High-cycle fatigue is a critical performance metric of structural alloys for many applications. The high cost, time, and labor involved in experimental fatigue testing call for efficient and accurate computer models o...
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Recently,significant efforts have been directed at overcoming the limitations of conventional rigid optoelectronic devices,particularly their poor mechanical stability under bending,folding,and stretching *** of major...
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Recently,significant efforts have been directed at overcoming the limitations of conventional rigid optoelectronic devices,particularly their poor mechanical stability under bending,folding,and stretching *** of major approaches for rendering optoelectronic devices mechanically deformable is to replace the conventional electronic/optoelectronic materials with functional nanomaterials or organic materials that are intrinsically flexible/***,advanced device designs and unconventional fabrication methods have also contributed to the development of soft optoelectronic ***,new devices such as bio-inspired curved image sensors,wearable light emitting devices,and deformable bio-integrated optoelectronic devices have been *** this review,recent progress in the development of soft optoelectronic materials and devices is ***,various materials such as nanomaterials,organic materials,and their hybrids that are suitable for developing deformable photodetectors,are ***,the nanomaterials and organic/polymeric materials that are applicable in deformable light-emitting diodes are ***,representative system-level applications of flexible and stretchable photodetectors and light-emitting diodes are reviewed,and future prospects are discussed.
It has been indicated 1 that the path forward for the widespread usage of ferroelectric (FE) materials may be considerably facilitated through the reduction of programming voltages to on-chip logic compatible values o...
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APtO3 (A = Ca, Sr, Ba) is a unique family in the complex transition metal oxides with the AMO3 formula. Most 3d and 4dAMO3 compounds adopt the perovskite structure when synthesized at ambient or high pressure; however...
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APtO3 (A = Ca, Sr, Ba) is a unique family in the complex transition metal oxides with the AMO3 formula. Most 3d and 4dAMO3 compounds adopt the perovskite structure when synthesized at ambient or high pressure; however, APtO3 perovskites have not been reported, even if their geometric tolerance factor, t, falls in the range suitable for the perovskite structure. Herein, we studied the crystal structures of BaPtO3 by performing the in situ x-ray diffraction over a broad range in the pressure (P)–temperature (T) phase diagram. The perovskite BaPtO3 can be stabilized at P>35 GPa and T>1100 K. A variety of crystal structures, including the perovskite structure and its hexagonal polytypes, observed in the P–T phase diagram of BaPtO3 match the structure predictions from the first-principles calculations reasonably well.
Characterization of structural diversity within soft materials is key for engineering new materials for various applications. Small-angle scattering (SAS) is a widely used characterization technique that provides stru...
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Characterization of structural diversity within soft materials is key for engineering new materials for various applications. Small-angle scattering (SAS) is a widely used characterization technique that provides structural information in soft materials at varying length scales (nm to microns). The typical output of a SAS measurement is the scattered intensity I(q) as a function of q, the scattered wavevector with respect to the incident wave. The scattered wavevector q is represented by its magnitude |q| ≡ q (in inverse distance units) and azimuthal angle θ. While structures with isotropic spatial arrangement can be interpreted by analysis of azimuthally averaged one-dimensional (1D) scattering profile, to understand anisotropic spatial arrangements, one has to interpret the two-dimensional (2D) scattering profile, I(q, θ). Manual interpretation of such 2D profiles is complicated, and usually involves fitting of approximate analytical models to azimuthally averaged sections of the 2D profile. In this paper, we present a new method called CREASE-2D that interprets, without any azimuthal averaging, the entire 2D scattering profile, I(q, θ), and outputs the relevant structural features. CREASE-2D is an extension of the ‘computational reverse engineering analysis for scatting experiments’ (CREASE) method that has been used successfully to analyze 1D SAS profiles for a variety of soft materials. CREASE uses a genetic algorithm for optimization and an artificial neural network (ANN) as the surrogate machine learning (ML) model for fast calculation of 1D ‘computed’ scattering profiles that are then compared to the experimental 1D scattering profiles in the optimization. CREASE-2D goes beyond CREASE by enabling analysis of 2D scattering profiles, which is far more challenging to interpret than the azimuthally averaged 1D profiles. Further, we use XGBoost as the surrogate ML model in CREASE-2D, in place of ANNs, to relate structural features to the I(q, θ) profile. The CREA
The increasing usage of antihelminthic drug mebendazole (MEB) in humans and livestock poses serious threat and is considered a significant environmental pollutant. Hence, monitoring the MEB residues in environmental s...
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