Multi-Level Switching of Spin-Torque Ferromagnetic Resonance in 2D Magnetite.

2D magnetic materials hold substantial promise in information storage and neuromorphic device applications. However, achieving a 2D material with high Curie temperature (T), environmental stability, and multi-level magnetic states remains a challenge. This is particularly relevant for spintronic devices, which require multi-level resistance states to enhance memory density and fulfil low power consumption and multi-functionality.

Room-temperature ferromagnetic CoSenanoplates synthesized by chemical vapor deposition.

Among novel two-dimensional materials, transition metal dichalcogenides (TMDs) with 3magnetic elements have been extensively researched owing to their unique magnetic, electric, and photoelectric properties. As an important member of TMDs, CoSeis an interesting material with controversial magnetic properties, hitherto there are few reports related to the magnetism of CoSematerials. Here, we report the synthesis of CoSenanoplates on AlOsubstrates by chemical vapor deposition (CVD).

Atomic structure and large magnetic anisotropy in air-sensitive layered ferromagnetic VI.

We report the air-sensitivity, atomic structure, and magnetic anisotropy of VI single crystals. We find that VI nanocrystals exhibit a large / ratio of around 0.75 and a uniaxial anisotropic constant of an order of 10 erg cc below the Curie temperature.

Medical expenditure for strabismus: a hospital-based retrospective survey.

Background And Aims: The misconception of the purpose of strabismus treatment has, on the one hand, affected the motivation of strabismus patients to seek care and, on the other hand, has resulted in strabismus not being covered by health insurance, both of which interact to limit the motivation of strabismus patients and also impose a financial burden on strabismus patients. Previous studies on the cost of strabismus had only addressed the cost utility and functional and psychosocial benefits of strabismus surgery. The aim of this study was to estimate the direct medical expenditure incurred for strabismus surgery and analyze the trend for the period 2014-2019 using the data collected by local eye hospitals in northeast China.

High-sensitivity and versatile plasmonic biosensor based on grain boundaries in polycrystalline 1L WS films.

Structural defects play an important role in exploitation of two-dimensional layered materials (2DLMs) for advanced biosensors with the increasingly high sensitivity and low detection limit. Grain boundaries (GBs), as an important type of structural defect in polycrystalline 2DLM films, potentially provide sufficient active defect sites for the immobilization of bioreceptor units via chemical functionalization. In this work, we report the selective functionalization of high-density GBs with complementary DNA receptors, via gold nanoparticle (AuNP) linkers, in wafer-scale polycrystalline monolayer (1L) W(Mo)S films as versatile plasmonic biosensing platforms.

Grain-boundary-rich polycrystalline monolayer WS film for attomolar-level Hg sensors.

Emerging two-dimensional (2D) layered materials have been attracting great attention as sensing materials for next-generation high-performance biological and chemical sensors. The sensor performance of 2D materials is strongly dependent on the structural defects as indispensable active sites for analyte adsorption. However, controllable defect engineering in 2D materials is still challenging.

Morphology-Tunable Synthesis of Intrinsic Room-Temperature Ferromagnetic γ-FeO Nanoflakes.

Intrinsic two-dimensional (2D) magnetic materials with room-temperature ferromagnetism and air stability are highly desirable for spintronic applications. However, the experimental observations of such 2D or ultrathin ferromagnetic materials are rarely reported owing to the scarcity of these materials in nature and for the intricacy in their synthesis. Here, we report a successful controllable growth of ultrathin γ-FeO nanoflakes with a variety of morphologies tunable by the growth temperature alone using a facile chemical vapor deposition method and demonstrate that all ultrathin nanoflakes still show intrinsic room-temperature ferromagnetism and a semiconducting nature.

Toward Efficient All-Polymer Solar Cells via Halogenation on Polymer Acceptors.

Although halogenation has been widely regarded as an effective approach to adjust the properties of organic semiconductors, systematic investigation on the comparison of nonhalogenated and halogenated polymer acceptors only received minor attention in all-polymer solar cell (all-PSC) community. Herein, we report three IDIC-based narrow band gap polymer acceptors, PIDIC2T, PIDIC2T2F, and PIDIC2T2Cl, which are composed of IDIC-C16 building blocks as acceptor units, linking pristine bithiophene, fluorinated bithiophene, or chlorinated bithiophene as donor units. Although these three polymer acceptors exhibit nearly identical lowest unoccupied molecular orbital (LUMO) levels of ca.

Giant Valley Coherence at Room Temperature in 3R WS with Broken Inversion Symmetry.

Breaking the space-time symmetries in materials can markedly influence their electronic and optical properties. In 3R-stacked transition metal dichalcogenides, the explicitly broken inversion symmetry enables valley-contrasting Berry curvature and quantization of electronic angular momentum, providing an unprecedented platform for valleytronics. Here, we study the valley coherence of 3R WS large single-crystal with thicknesses ranging from monolayer to octalayer at room temperature.

Grain wall boundaries in centimeter-scale continuous monolayer WS film grown by chemical vapor deposition.

Centimeter-scale continuous monolayer WS film with large tensile strain has been successfully grown on oxidized silicon substrate by chemical vapor deposition, in which monolayer grains can be more than 200 μm in size. Monolayer WS grains are observed to merge together via not only traditional grain boundaries but also non-traditional ones, which are named as grain walls (GWs) due to their nanometer-scale widths. The GWs are revealed to consist of two or three layers.

Electric-Field Control of Spin-Orbit Torques in WS/Permalloy Bilayers.

Transition metal dichalcogenides (TMDs) have drawn great attention owing to their potential for electronic, optoelectronic, and spintronic applications. In TMDs/ferromagnetic bilayers, an efficient spin current can be generated by the TMDs to manipulate the magnetic moments in the ferromagnetic layer. In this work, we report on the electric-field modulation of spin-orbit torques (SOTs) in WS/NiFe bilayers by the spin-torque ferromagnetic resonance technique.

Ultrahigh-Gain and Fast Photodetectors Built on Atomically Thin Bilayer Tungsten Disulfide Grown by Chemical Vapor Deposition.

The low responsivity observed in photodetectors based on monolayer transition-metal dichalcogenides has encouraged the pursuit of approaches that can efficiently enhance the external quantum efficiency, which relies predominantly on the light absorption, the lifetime of the excess carriers, and the charge collection efficiency. Here, we demonstrate that phototransistors fabricated on large-area bilayer tungsten disulfide (WS) grown by chemical vapor deposition exhibit remarkable performance with photoresponsivity, photogain, and detectivity of up to ∼3 × 10 A/W, 1.4 × 10, and ∼5 × 10 Jones, respectively.

Strain Release Induced Novel Fluorescence Variation in CVD-Grown Monolayer WS Crystals.

Tensile strain is intrinsic to monolayer crystals of transition metal disulfides such as Mo(W)S grown on oxidized silicon substrates by chemical vapor deposition (CVD) owing to the much larger thermal expansion coefficient of Mo(W)S than that of silica. Here we report fascinating fluorescent variation in intensity with aging time in CVD-grown triangular monolayer WS crystals on SiO (300 nm)/Si substrates and formation of interesting concentric triangular fluorescence patterns in monolayer crystals of large size. The novel fluorescence aging behavior is recognized to be induced by the partial release of intrinsic tensile strain after CVD growth and the induced localized variations or gradients of strain in the monolayer crystals.

Highly sensitive and fast monolayer WS phototransistors realized by SnS nanosheet decoration.

Two-dimensional chalcogenide monolayers are strong candidates for next-generation flexible and transparent optoelectronics. Due to the intrinsic ultrathin thickness and limited optical absorption, however, their responsivity is normally low. Here we develop a simple and low-cost method to fabricate high-performance hybrid phototransistors of monolayer WS with significantly enhanced responsivity and an extended spectral response range, by virtue of surface decoration with liquid-phase exfoliated SnS nanosheets (NSs).

Enhanced Photoresponse of SnSe-Nanocrystals-Decorated WS2 Monolayer Phototransistor.

Single-layer WS2 has shown excellent photoresponse properties, but its promising applications in high-sensitivity photodetection suffer from the atomic-thickness-limited adsorption and band-gap-limited spectral selectivity. Here we have carried out investigations on WS2 monolayer based phototransistors with and without decoration of SnSe nanocrystals (NCs) for comparison. Compared to the solely WS2 monolayer, SnSe NCs decoration leads to not only huge enhancement of photoresponse in visible spectrum but also extension to near-infrared.

Observation of Strong Interlayer Coupling in MoS2/WS2 Heterostructures.

Epitaxial growth of A-A and A-B stacking MoS2 on WS2 via a two-step chemical vapor deposition method is reported. These epitaxial heterostructures show an atomic clean interface and a strong interlayer coupling, as evidenced by systematic characterization. Low-frequency Raman breathing and shear modes are observed in commensurate stacking bilayers for the first time; these can serve as persuasive fingerprints for interfacial quality and stacking configurations.

Grape seed proanthocyanidin extract protects human lens epithelial cells from oxidative stress via reducing NF-кB and MAPK protein expression.

Purpose: Oxidative damage induced by H₂O₂ treatment can irreversibly damage the lens epithelium, resulting in cell death and cataract. Grape seed extract (GSE) is a widely consumed dietary supplement that has the capability to scavenge oxidants and free radicals. GSE contain 70%-95% standardized proanthocyanidins.

Ocular pharmacokinetic study on baicalin in lens of rabbits following intragastric administration.

Purpose: This paper is to study the pharmacokinetic features of baicalin in lens through observing baicalin's concentration changes in lens of rabbits following intragastric administration.

Methods: Forty-four rabbits were randomly divided into 11 groups. The lens were collected at the beginning without any intragastric administration, and then collected after 15 minutes following intragastric administration of 80 mg/kg baicalin, and continually collected individually after 0.