Ferro-valleytricity that manifests spin-orbit coupling (SOC)-induced spontaneous valley polarization is generally considered to occur in two-dimensional (2D) materials with out-of-plane spin magnetization. Here, we propose a mechanism to realize SOC-induced valley polarization and ferro-valleytricity in 2D materials with in-plane spin magnetization, wherein the physics correlates to non-collinear magnetism in triangular lattice. Our model analysis provides comprehensive ingredients that allow for ferro-valleytricity with in-plane spin magnetization, revealing that mirror symmetry favors remarkable valley polarization and time-reversal-mirror joint symmetry should be excluded.
View Article and Find Full Text PDFAmyloid β peptide (Aβ) induces neurodegeneration in the early stage of Alzheimer's disease (AD), resulting in neuroinflammation, oxidative damage, and mitochondrial impaired function. These reactions were closely associated with the pathological changes of brain microglia. Therefore, it was crucial to investigate the precise process of neuroinflammation induced by Aβ in microglia and discover therapies to alleviate its harmful consequences.
View Article and Find Full Text PDFInspired by recent studies on MoS and MoSiN, we propose and investigate Janus MoBXY (X = N, P; Y = S, Se, Te) monolayers, which exhibit robust dynamic and thermal stabilities. Our findings reveal that all these monolayers are semiconductors, with MoBNS and MoBPTe exhibiting direct band gaps at the K/K' points, resulting in degenerate valleys and significant valley spin splitting (VSS) in the valence band. Notably, Berry curvatures at K and K' points, with opposite signs, suggest potential for inducing the valley Hall effect (VHE).
View Article and Find Full Text PDFValley multiferroicity, coupled with ferro-valleytricity and primary ferroicities in a single phase, is of fundamental significance in condensed-matter physics and materials science, as it provides a convenient route to reverse the anomalous valley Hall (AVH) effect. Current research in this field focuses mainly on ferromagnetic ferro-valleytricity, whereas ferroelectric ferro-valleytricity is seldom explored. Here, using symmetry arguments and tight-binding model analysis, we report a novel mechanism of coupling ferro-valleytricity with ferroelectricity, , single-phase valley multiferroicity, in a two-dimensional magnetic lattice.
View Article and Find Full Text PDFRealizing the anomalous valley Hall (AVH) effect in two-dimensional (2D) materials is of crucial importance for information processing and recording technology. While the research in this field mainly focuses on ferromagnetic systems, little is known about antiferromagnetic systems. Here, using model analysis, we report a novel mechanism of realizing the AVH effect in 2D antiferromagnetic materials.
View Article and Find Full Text PDFControl over and manipulation of valley physics ferrovalleytricity is highly desirable for advancing valleytronics. Current research focuses primarily on two-dimensional ferromagnetic systems, while antiferromagnetic counterparts are seldom explored. Here, we present a general mechanism for extending the ferrovalleytricity paradigm to antiferromagnetic lattices to achieve spin control over valley physics.
View Article and Find Full Text PDFEngineering the valley index is essential and highly sought for valley physics, but currently, it is exclusively based on the paradigm of the challenging ferrovalley with spin-orientation reversal under a magnetic field. Here, an alternative strategy, i.e.
View Article and Find Full Text PDFSkyrmion-bimeron switching is one of the most important phenomena in topological magnetism. Currently, it is usually realized by the annoying spin orientation vertical-reversal through magnetic field. Based on first-principles calculations and atomic spin simulations, we alternatively unveil that the switching between magnetic skyrmions and bimerons can be achieved in topological magnetic monolayer CrSeBr by external strain.
View Article and Find Full Text PDFNanomaterials with photoresponsivity have garnered attention due to their fluorescence imaging, photodynamic, and photothermal therapeutic properties. In this study, a photoresponsivity nanoassembly was developed by using photosensitizers and carbon dots (CDs). Due to their multiple excitation peaks and multicolor fluorescence emission, especially their membrane-permeating properties, these nanoassemblies can label cells with multiple colors and track cell imaging in real time.
View Article and Find Full Text PDFCoupling the spin Hall effect with novel degrees of freedom of electrons is central to the rich phenomena observed in condensed-matter physics. Here, using symmetry analysis and a low-energy model, we report the sliding ferroelectricity engineered coupling between spin Hall effect and emerging layertronics, thereby generating the layer spin Hall effect (LSHE), in a 2D lattice. The physics is rooted in a pair of -symmetry connected valleys, which experience spin splitting accompanied by large Berry curvature under spin-orbit coupling.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
April 2024
Understanding water absorption mechanisms of sand-fixing plants is important for the rational establishment of plant community structures, thereby providing a scientific basis for desertification control and the efficient utilization of water resources in sandy areas. Based on the hydrogen and oxygen isotopic compositions of precipi-tation, soil water, xylem water, and groundwater, coupled with soil water-heat dynamics, annual water consumption characteristics of vegetation, using the multi-source linear mixing model (IsoSource), we analyzed the differences in water sources between and , during winter and the growing season. We further examined the effects of groundwater depth (2 m and 10 m), soil freezing-thawing, and drought on their water utilization to elucidate water absorption mechanisms of those species.
View Article and Find Full Text PDFLayertronics, rooted in the layer Hall effect (LHE), is an emerging fundamental phenomenon in condensed matter physics and spintronics. So far, several theoretical and experimental proposals have been made to realize LHE, but all are based on antiferromagnetic systems. Here, using symmetry and tight-binding model analysis, we propose a general mechanism for engineering layertronics in a two-dimensional ferromagnetic multiferroic lattice.
View Article and Find Full Text PDFPhys Chem Chem Phys
February 2024
Magnetic skyrmions and their effective manipulations are promising for the design of next-generation information storage and processing devices, due to their topologically protected chiral spin textures and low energy cost. They, therefore, have attracted significant interest from the communities of condensed matter physics and materials science. Herein, based on density functional theory (DFT) calculations and micromagnetic simulations, we report the spontaneous 2 nm-diameter magnetic skyrmions in the monolayer CuCrPTe originating from the synergistic effect of broken inversion symmetry and strong Dzyaloshinskii-Moriya interactions (DMIs).
View Article and Find Full Text PDFThe van der Waals (vdWs) heterostructures, with vertical layer stacking structure of various two-dimensional (2D) materials, maintain the reliable photonic characteristics while compensating the shortcomings of the participating individual components. In this work, we combine the less-studied multilayer tin selenide (SnSe) thin film with one of the traditional 2D materials, graphene, to fabricate the graphene-based vdWs optical switching element (Gr-SnSe) with superior broadband nonlinear optical response. The transient absorption spectroscopy (TAS) measurement results verify that graphene acts as the recombination channel for the photogenerated carrier in the Gr-SnSe sample, and the fast recovery time can be reduced to hundreds of femtoseconds which is beneficial for the optical modulation process.
View Article and Find Full Text PDFIn the field of physics and materials science, the discovery of the layer-polarized anomalous Hall effect (LP-AHE) stands as a crucial development. The current research paradigm is rooted in topological or inversion-asymmetric valleytronic systems, making such a phenomenon rather rare. In this work, a universal design principle for achieving the LP-AHE from inversion-symmetric single-layer lattices is proposed.
View Article and Find Full Text PDFIntroduction: The impact of groundwater table depth (GTD) on bacterial communities and soil nutrition in revegetated areas remains unclear.
Methods: We investigated the impacts of plant growth and soil physicochemical factors on rhizosphere bacterial communities under different GTD.
Results: The four plant growth indices (Pielou, Margalef, Simpson, and Shannon-Wiener indices) and soil water content (SWC) at the Artem and Salix sites all showed a decreasing trend with increasing GTD.
Owing to the extremely limited structural deformation caused by the introduction of guest ions that their rigid structure can sustain, crystalline materials typically fail owing to structural collapse when utilized as electrode materials. Amorphous materials, conversely, are more resistant to volume expansion during dynamic ion transport and can introduce a lot of defects as active sites. Here, The amorphous polyaniline-coated/intercalated VO·nHO (PVOH) nanowires are prepared by in situ chemical oxidation combined with self-assembly strategy, which exhibited impressive electrochemical properties because of its short-range ordered crystal structure, oxygen vacancy/defect-rich, improved electronic channels, and ionic channels.
View Article and Find Full Text PDFElectrocatalytic urea synthesis through N + CO coreduction and C-N coupling is a promising and sustainable alternative to harsh industrial processes. Despite considerable efforts, limited progress has been made due to the challenges of breaking inert N≡N bonds for C-N coupling, competing side reactions, and the absence of theoretical principles guiding catalyst design. In this study, we propose a mechanism for highly electrocatalytic urea synthesis using two adsorbed N molecules and CO as nitrogen and carbon sources, respectively.
View Article and Find Full Text PDFPolymer micelles/vesicles made of a red-light-responsive Ru(II)-containing block copolymer (PolyRu) are elaborated as a model system for anticancer phototherapy. PolyRu is composed of PEG and a hydrophobic polypeptoid bearing thioether side chains, 40% of which are coordinated with [Ru(2,2':6',2″-terpyridine)(2,2'-biquinoline)](PF) via the Ru-S bond, resulting in a 67 wt % Ru complex loading capacity. Red-light illumination induces the photocleavage of the Ru-S bond and produces [Ru(2,2':6',2″-terpyridine)(2,2'-biquinoline)(HO)](PF).
View Article and Find Full Text PDFPhotocatalytic and electrocatalytic reactions to produce value-added chemicals offer promising solutions for addressing the energy crisis and environmental pollution. Photocatalysis is driven by light excitation and charge separation and relies on semiconducting catalysts, while electrocatalysis is driven by external electric current and is mostly based on metallic catalysts with high electrical conductivity. Due to the distinct reaction mechanism, the conversion between the two catalytic types has remained largely unexplored.
View Article and Find Full Text PDFSci Total Environ
January 2024
Clarifying the dependence of the grassland water budget change and its components on environmental factors is significant for the sustainable development of dryland ecosystems. Here, the Hydrus-1D model was used to simulate the water budget of natural grassland for 42 years (1980-2021). The standardized precipitation evapotranspiration index (SPEI) and soil moisture deficit index (SMDI) were used to analyze the soil drought evolution characteristics and the water use dynamic of the grassland in dry and wet years.
View Article and Find Full Text PDFMagnetic skyrmions in two-dimensional lattices are a prominent topic of condensed matter physics and materials science. Current research efforts in this field are exclusively constrained to Néel-type and antiskyrmions, while Bloch-type magnetic skyrmions are rarely explored. Here, we report the discovery of Bloch-type magnetic skyrmions in a two-dimensional lattice of MnInPTe, using first-principles calculations and Monte-Carlo simulations.
View Article and Find Full Text PDFMagnetic skyrmions are topologically protected entities that are promising for information storage and processing. Currently, an essential challenge for future advances of skyrmionic devices lies in achieving effective control of skyrmion properties. Here, through first-principles and Monte-Carlo simulations, we report the identification of nontrivial topological magnetism in two-dimensional multiferroics of CoNF.
View Article and Find Full Text PDFElectro-mechanical coupling is of great interest for applications in sensors, actuators and energy harvesters. While the control of electrical charge by mechanical force has been studied extensively, reverse coupling is rarely explored, especially in two-dimensional (2D) lattices. Herein, we propose a novel mechanism for electro-mechanical coupling that realizes the electric field switching of the dimensions of a 2D lattice in a reversible and nonvolatile fashion, through the mediated strength of interlayer interactions in ferroelectric bilayer systems.
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