Designing Chiral Organometallic Nanosheets with Room-Temperature Multiferroicity and Topological Nodes.

Two-dimensional (2D) room-temperature chiral multiferroic and magnetic topological materials are essential for constructing functional spintronic devices, yet their number is extremely limited. Here, by using the chiral and polar HPP (HPP = 4-(3-hydroxypyridin-4-yl)pyridin-3-ol) as an organic linker and transition metals (TM = Cr, Mo, W) as nodes, we predict a class of 2D TM(HPP) organometallic nanosheets that incorporate homochirality, room-temperature magnetism, ferroelectricity, and topological nodes. The homochirality is introduced by chiral HPP linkers, and the change in structural chirality induces a topological phase transition of Weyl phonons.

The type-I, III nodal ring, type-I, III quadratic nodal point, and Dirac valley phonons in 2D kagome lattices MC(M = As, Bi, Cd, Hg, P, Sb, Zn).

Topological phases in kagome systems have garnered considerable interest since the introduction of the colloidal kagome lattice. Our study employs first-principle calculations and symmetry analysis to predict the existence of ideal type-I, III nodal rings (NRs), type-I, III quadratic nodal points (QNPs), and Dirac valley phonons (DVPs) in a collection of two-dimensional (2D) kagome lattices MC(M = As, Bi, Cd, Hg, P, Sb, Zn). Specifically, the Dirac valley points (DVPs) can be observed at two inequivalent valleys with Berry phases of +and-π, connected by edge arcs along the zigzag and armchair directions.

Optimizing skyrmionium movement and stability stray magnetic fields in trilayer nanowire constructs.

Skyrmioniums, known for their unique transport and regulatory properties, are emerging as potential cornerstones for future data storage systems. However, the stability of skyrmionium movement faces considerable challenges due to the skyrmion Hall effect, which is induced by deformation. In response, our research introduces an innovative solution: we utilized micro-magnetic simulations to create a sandwiched trilayer nanowire structure augmented with a stray magnetic field.

Adaptive anisotropic pixel-by-pixel correction method for a space-variant degraded image.

Large field-of-view optical imaging systems often face challenges in the presence of space-variant degradation. The existence of degradation leads to target detection and recognition being difficult or even unsuccessful. To address this issue, this paper proposes an adaptive anisotropic pixel-by-pixel space-variant correction method.

Control and regulation of skyrmionic topological charge in a novel synthetic antiferromagnetic nanostructure.

Skyrmionium is a combination of a skyrmion with a topological charge ( is +1 or -1), resulting in a magnetic configuration with a total topological charge of = 0. Skyrmionium has distinctive characteristics, including a slightly higher velocity, motion restricted to the middle of the track without the skyrmion Hall effect (SkHE), and absence of an acceleration phase. However, there is little stray field due to the zero net magnetization, the topological charge is zero due to the magnetic configuration, and detecting skyrmionium is still challenging.

Domain wall motion driven by a wide range of current in coupled soft/hard ferromagnetic nanowires.

Racetrack memory with the advantages of small size and high reading speed is proposed based on current-induced domain wall (DW) motion in a ferromagnetic (FM) nanowire. Walker breakdown that restricts the enhancement of DW velocity in a single FM nanowire can be depressed by inter-wire magnetostatic coupling in a double FM nanowire system. However, this magnetostatic coupling also limits the working current density in a small range.

High-performance broadband photodetectors based on all-inorganic perovskite CsPb(Br/I) nanocrystal/CdS-microwire heterostructures.

High-performance broadband photodetectors that can operate at UV, visible, and near-infrared wavelengths have been fabricated based on CsPb(Br/I) nanocrystal (NC)/CdS-microwire (MW) heterostructures. Under an incident light illumination of 365, 530, and 660 nm, the CsPb(Br/I)-NC/CdS-MW-heterostructure-based photodetector exhibited a superior photosensitivity and broader spectral response than those of a bare-CdS-MW-based photodetector, which can be attributed to the light-trapping ability of the CsPb(Br/I) NCs and charge-transfer efficiency at the CsPb(Br/I)-NC/CdS-MW-heterojunction interface. The photodetector based on the CsPb(Br/I) NC/CdS-MW heterostructure also exhibited a good response to near-infrared light (760 and 810 nm) because the produced heterojunction facilitates the spatial separation of the photogenerated carriers, and the carriers are transferred from the CsPb(Br/I) NC part to the CdS MW part through diffusion due to the relatively long diffusion length in the CsPb(Br/I) layer.

Spin-Seebeck effect and thermoelectric properties of one-dimensional graphene-like nanoribbons periodically embedded with four- and eight-membered rings.

The spin-Seebeck effect together with a high spin thermoelectric conversion efficiency has been regarded as one of the core topics in spin caloritronics. In this work, we propose a spin caloritronic device constructed on hydrogen-terminated sawtooth graphene-like nanoribbons periodically embedded with four- and eight-membered rings to investigate the thermal spin currents and thermoelectric properties by using density functional theory combined with the non-equilibrium Green's function method. Our theoretical results show that spin-Seebeck currents are induced by the temperature gradient between two leads due to two isolated spin-up and spin-down transport channels above or below the Fermi level.

Structure-Adjustable Gold Nanoingots with Strong Plasmon Coupling and Magnetic Resonance for Improved Photocatalytic Activity and SERS.

Au nanoingots, on which an Au nanosphere is accurately placed in an open Au shell, are synthesized through a controllable hydrothermal method. The prepared Au nanoingots exhibit an adjustable cavity structure, strong plasmon coupling, tunable magnetic plasmon resonance, and prominent photocatalytic and SERS performances. Au nanoingots exhibit two resonance peaks in the extinction spectrum, one (around 550 nm) is ascribed to electric dipole resonance coming from the central Au, and the other one (650-800 nm) is ascribed to the magnetic dipole resonance originating from the open Au shell.

Multi-interfacial plasmon coupling in multigap (Au/AgAu)@CdS core-shell hybrids for efficient photocatalytic hydrogen generation.

Plasmon coupling induced intense light absorption and near-field enhancement have vast potential for high-efficiency photocatalytic applications. Herein, (Au/AgAu)@CdS core-shell hybrids with strong multi-interfacial plasmon coupling were prepared through a convenient strategy for efficient photocatalytic hydrogen generation. Bimetallic Au/AgAu cores with an adjustable number of nanogaps (from one to four) were primarily synthesized by well-controlled multi-cycle galvanic replacement and overgrowth processes.

Graphene Aerogel Broken to Fragments for a Piezoresistive Pressure Sensor with a Higher Sensitivity.

The porous and elastic reduced graphene aerogel (rGA) is a promising active material for piezoresistive pressure sensors (PRSs) to realize an electronic skin. Due to the specific working mechanism and the limitation of the rGA's monolithic conductive network, the PRSs based on rGA suffer from a limited change of resistance with mechanical deformation, so they show poor sensitivity and cannot detect low pressures. Here we aim to improve the sensitivity of the PRS and make it suitable for a low-pressure system (0.

MoS-Based Photodetectors Powered by Asymmetric Contact Structure with Large Work Function Difference.

Self-powered devices are widely used in the detection and sensing fields. Asymmetric metal contacts provide an effective way to obtain self-powered devices. Finding two stable metallic electrode materials with large work function differences is the key to obtain highly efficient asymmetric metal contacts structures.

Controlled Growth of an Mo₂C-Graphene Hybrid Film as an Electrode in Self-Powered Two-Sided Mo₂C-Graphene/Sb₂SSe/TiO₂ Photodetectors.

The monotonic work function of graphene makes it difficult to meet the electrode requirements of every device with different band structures. Two-dimensional (2D) transition metal carbides (TMCs), such as carbides in MXene, are considered good candidates for electrodes as a complement to graphene. Carbides in MXene have been used to make electrodes for use in devices such as lithium batteries.

The half-metallicity and the spin filtering, NDR and spin Seebeck effects in 2D Ag-doped SnSe monolayer.

Two-dimensional SnSe has become more and more attractive due to the excellent electronic, optoelectronic, and thermoelectric properties. However, the study on magnetic properties is rare. Inspired by the recent experimental synthesis of SnSe monolayer and Ag-doped SnSe thin films, we use the first-principles calculations combined with the nonequilibrium Green's function method to investigate the structural, electronic, magnetic, and spin transport properties of an Ag-doped SnSe monolayer.

Robust antiferromagnetism preventing superconductivity in pressurized (Ba 0.61 K 0.39)Mn2Bi2.

BaMn2Bi2 possesses an iso-structure of iron pnictide superconductors and similar antiferromagnetic (AFM) ground state to that of cuprates, therefore, it receives much more attention on its properties and is expected to be the parent compound of a new family of superconductors. When doped with potassium (K), BaMn2Bi2 undergoes a transition from an AFM insulator to an AFM metal. Consequently, it is of great interest to suppress the AFM order in the K-doped BaMn2Bi2 with the aim of exploring the potential superconductivity.

Effect of pressure on heterocyclic compounds: pyrimidine and s-triazine.

We have examined the high-pressure behaviors of six-membered heterocyclic compounds of pyrimidine and s-triazine up to 26 and 26.5 GPa, respectively. Pyrimidine crystallizes in Pna2₁ symmetry (phase I) with the freezing pressure of 0.

Garnet-to-perovskite transition in Gd3Sc2Ga3O12 at high pressure and high temperature.

The structural phase transition of gadolinium-scandium-gallium garnet (Gd(3)Sc(2)Ga(3)O(12), GSGG) has been studied at high pressure and high temperature using the synchrotron X-ray diffraction technique in a laser-heated diamond anvil cell. The GSGG garnet transformed to an orthorhombic perovskite structure at approximately 24 GPa after laser heating to 1500-2000 K. The garnet-to-perovskite phase transition is associated with an ∼8% volume reduction and an increase in the coordination number of the Ga(3+) or Sc(3+) ion.

Pressure-induced structural change in orthorhombic perovskite GdMnO3.

Structural stability of the perovskite-type GdMnO(3) has been investigated by the synchrotron angle-dispersive x-ray diffraction technique up to 63 GPa in a diamond anvil cell. GdMnO(3) stays in an orthorhombic structure but undergoes an isostructural phase transition with ~5% volume reduction at 50 GPa. In the parent orthorhombic phase, the compressions along a, b and c axes exhibit a large anisotropic behavior.