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Cubic materials host high crystal symmetry and hence are not expected to support anisotropy in transport phenomena. In contrast to this common expectation, here we report an anomalous anisotropy of spin current can emerge in the (001) film of Mn 3 Pt, a noncollinear antiferromagnetic spin source with face-centered cubic structure. Such spin current anisotropy originates from the intertwined time reversal-odd ( T -odd) and time reversal-even ( T -even) spin Hall effects. Based on symmetry analyses and experimental characterizations of the current-induced spin torques in Mn 3 Pt-based heterostructures, we find that the spin current generated by Mn 3 Pt (001) exhibits exotic dependences on the current direction for all the spin components, deviating from that in conventional cubic systems. We also demonstrate that such an anisotropic spin current can be used to realize low-power spintronic applications such as the efficient field-free switching of the perpendicular magnetizations. Symmetry is an essential ingredient that governs numerous physical phenomena, including spin transport. Following this principle, spin current sources with a highly symmetric cubic structure are not expected to support anisotropic spin currents. Here, the authors demonstrate an anomalous spin current anisotropy in a cubic noncollinear antiferromagnet Mn 3 Pt by exploiting the combination of conventional and magnetic spin-hall effects.

A novel Z-scheme Bi 2 MoO 6 /Bi 12 SiO 20 (MS) heterojunction, with 2D nanoplates of Bi 2 MoO 6 anchored on the surface of flower-shaped Bi 12 SiO 20 particles, was synthesized via simple solvothermal process for the first time. A series of techniques including XRD, XPS, SEM, TEM, BET, UV–vis DRS and Mott–Schottky were used for characterizing the photocatalysts. The MS 0.6 (the heterojunction with a Bi 2 MoO 6 /MS mass ratio of 0.6:1) exhibited optimal photocatalytic activity for degrading RhB, and the reaction rate constant achieved 0.041 min −1 , which was 41 and 4.6 times that of Bi 12 SiO 20 and Bi 2 MoO 6 , respectively. The MS 0.6 also presents outstanding activity for the degradation of BPA (0.014 min −1 ), which was 3.5 and 14 times that of Bi 12 SiO 20 and Bi 2 MoO 6 , respectively. Furthermore, the UV–vis absorption spectrum and TOC test confirmed that the mineralization capacity of Bi 2 MoO 6 was significantly enhanced after coupling with Bi 12 SiO 20 . The enhanced performance was attributed to the improved light absorption and excellent separation efficiency of photo-induced carriers. Trapping and ESR experiments indicated that h + and •O 2 − jointly dominated the degradation of RhB. Therefore, a reliable Z-scheme mechanism was proposed. Additionally, MS 0.6 presented a good stability and durability in four catalytic runs. This study provides an insight for designing highly efficient Z-scheme Bi 12 SiO 20 -based photocatalysts for the practical sewage disposal. Graphical abstract

Oral squamous cell carcinoma (OSCC) frequently develops within chronically injured oral mucosa and may be preceded by clinically recognizable oral potentially malignant disorders (OPMDs), which provide an important window for cancer interception. This review examines how etiological exposures, persistent inflammation, and lesion-specific epithelial-stromal-immune interactions cooperate during the transition from mucosal injury to dysplasia, carcinoma in situ, and invasive OSCC. Major carcinogenic exposures, including tobacco, alcohol, and areca nut, are considered together with context-dependent contributors such as microbial dysbiosis, viral infection, and immune-mediated epithelial injury. At the molecular level, inflammation-driven oral carcinogenesis involves cytokine and chemokine amplification, oxidative and nitrosative stress, NF-κB and STAT3 activation, the COX-2/PGE axis, genomic instability, field cancerization, epithelial-stromal crosstalk, angiogenesis, immune dysregulation, and epigenetic and non-coding RNA-mediated reprogramming. Emerging tools such as molecular risk assessment, liquid biopsy, optical imaging, spatially resolved profiling, and artificial intelligence-assisted models may improve identification of high-risk lesions, although most biomarkers require further prospective validation. Prevention should therefore integrate exposure control, biopsy-based diagnosis, local treatment when indicated, long-term surveillance, and trial-based precision strategies according to lesion risk, intervention window, and safety profile. This review supports a shift from lesion-centered management toward risk-adapted precision prevention in inflammation-driven oral carcinogenesis.

Fourfold exchange anisotropy has recently been discovered in bilayers consisting of a ferromagnetic (FM) layer exchange-coupling with an epitaxial antiferromagnetic (AF) layer. The chemical ordering of the AF layer plays an important role in the interfacial exchange coupling of AF/FM bilayers. Herein, we studied the thickness dependence of the chemical ordering and fourfold exchange anisotropy of FeRh/CoFe bilayers before and after the AF–FM phase transition of FeRh. The chemical ordering parameter of FeRh obtained by x-ray diffraction increases with thickness due to the decrease in the proportion of low-order interfaces, which results in an increase in the magnetic phase transition temperature and a decrease in the phase transition width, residual magnetization in the AF state, and lattice constant. After the occurrence of the AF–FM phase transition, the fourfold exchange anisotropy observed in the CoFe layer by magneto-optical Kerr effect changes from the FeRh〈110〉 to 〈100〉 directions, indicating the orientation change in the cubic magnetocrystalline anisotropy of FeRh. The fourfold exchange anisotropy measured by ferromagnetic resonance continues to increase with the FeRh thickness, indicating an effective thickness by far larger than that of chemically disordered AF systems. The FeRh/FM exchange coupling is highly dependent on chemical ordering, not only on the low-order surface of a few nanometers but also on the high-order interior extending to a depth of tens of nanometers.

Exchange bias (EB) occurring in ferromagnetic (FM)/antiferromagnetic (AFM) bilayers conventionally can lead to a unidirectional magnetic anisotropy ( K eb ) as well as an accompanied uniaxial magnetic anisotropy ( K u ). We observed an additional fourfold magnetic anisotropy ( K 4 ) induced by interfacial exchange coupling in amorphous CoFeB/epitaxial IrMn bilayers with an EB. Because of the combined effect of the three kinds of magnetic anisotropies, one- and two-step magnetic switching processes were observed at different magnetic field orientations, which usually appear in single-crystal FM layer with an intrinsic magnetocrystalline anisotropy but not in amorphous FM layer. The angular dependent magnetic switching fields can be nicely fitted by a phenomenological model based on domain wall nucleation and propagation with the in-plane K 4 along . The ferromagnetic resonance measurements indicate that the specific strength of K 4 for EB along [100] is larger than that for EB along [110]. The induced K 4 can be understood by considering two types of AFM domains caused by both monatomic steps and defects and their induced net uncompensated spins along the in-plane axes. The different dependence of K 4 on the EB direction are because of the different effects of growth magnetic field on the presence of AFM domains.

β-Bi 2 O 3 /(BiO) 4 (OH) 2 CO 3 composite was first prepared by using NaBiO 3 ·2H 2 O as a precursor via solvothermal method. X-ray diffraction, scanning electron microscope, high-resolution transmission electron microscope, and UV–Vis diffuse reflectance spectrum have been used to characterize the composite material. It was found that the volume ratio of ethanol to water plays a vital role in the formation of (BiO) 4 (OH) 2 CO 3 and the formation mechanism of β-Bi 2 O 3 /(BiO) 4 (OH) 2 CO 3 composite has been investigated in this paper. Additionally, the as-prepared β-Bi 2 O 3 /(BiO) 4 (OH) 2 CO 3 heterojunction exhibited superior photocatalytic activity for the degradation of contaminants. 91.1% of Rhodamine B (RhB), 81.6% of Congo red, and 89.4% of tetracycline hydrochloride (TC) can be degraded in 70 min, 180 min and 160 min under the simulated sunlight irradiation, respectively. Furthermore, the apparent rate constant values of β-Bi 2 O 3 /(BiO) 4 (OH) 2 CO 3 are approximately 10 times that of β-Bi 2 O 3 and about 3 times that of (BiO) 4 (OH) 2 CO 3 . 75.9% of RhB can still be degraded by Bi 2 O 3 /(BiO) 4 (OH) 2 CO 3 in the process of third cycling run. The trapping experiments of active species indicated that holes (h + ) and superoxide radicals (·O 2 − ) were the major active species during the degradation process. This study provides new insights into design and synthesis of heterojunction photocatalysts for environmental remediation.

In this paper, δ-Bi 2 O 3 /Bi 4 O 7 heterojunction composites were successfully formed through hydrothermal reactions. The special morphology of rod-like Bi 4 O 7 bonded with nanoparticles δ-Bi 2 O 3 was observed by SEM and TEM, and BET results exhibited that the special surface area of the composite was increased slightly. The enhanced photocatalytic activity was mainly attributed to the construction of heterojunctions at the interface. Compared with two single phase samples, δ-Bi 2 O 3 /Bi 4 O 7 exhibited much better photocatalytic efficiency in photocatalytic degradation of organic pollutants under visible light excitation. Especially, the composite BO-2 (the addition amount of δ-Bi 2 O 3 was 0.25 mmol) showed the maximum removal rate for RhB (0.07275 min −1 ), which was 12.92 and 2.53 times that of δ-Bi 2 O 3 and Bi 4 O 7 , respectively. Similarly, the composite showed an excellent removal rate (0.01042 min −1 ) for phenol, which was 13.71 and 1.77 times that of δ-Bi 2 O 3 and Bi 4 O 7 , respectively. Further, TOC test confirmed that the mineralization ability of the composite was significantly improved with the successful construction of the heterojunction. Besides, the photocatalytic circulation tests showed the favorable stability of δ-Bi 2 O 3 /Bi 4 O 7 , and the trapping agent experiment verified the main active substances during photocatalytic, which were h + and · O 2 − . In addition, the electrochemical experiments results showed that the separation and migration ability of carriers was significantly improved due to the successful establishment of heterojunction. Consequently, a probable mechanism for organic contaminants degradation over δ-Bi 2 O 3 /Bi 4 O 7 heterojunction was also proposed, which may spur a growth on Bi 4 O 7 based heterojunction photocatalyst.

Modulable electronic and magnetic structures significantly extend the properties and applications of two-dimensional (2D) materials. 2D antiferromagnets (AFM) can even become ferromagnets (FM) by various approaches, which ignites growing research interests in 2D AFM. Through first-principles calculations, we find that the adsorption of Li (electron doping) and F (hole doping) on the surface of MnPSe 3 can induce half-metallicity with opposite spin polarizations. The adsorption site, concentration, charge transfer, and the exchange energy are investigated in detail, indicating the robustness of half-metallicity. At the interface of MnPS 3 /Au(111) heterostructure, we find electrons transfer from Au(111) to MnPS 3 , forming the Ohmic contact and inducing AFM-FM transition. All our results show that ferromagnetic MnPX 3 (X = S and Se) monolayer with half-metallicity can be easily obtained, which may be of great significance in 2D spintronic materials and devices.

Magnetic anisotropy is a fundamental key parameter of magnetic materials that determines their applications. For ferromagnetic materials, the magnetic anisotropy can be easily detected by using conventional magnetic characterization techniques. However, due to the magnetic compensated structure in antiferromagnetic materials, synchrotron measurements, such as X-ray magnetic linear dichroism, are often needed to probe their magnetic properties. In this work, we observed an imprinted fourfold magnetic anisotropy in the amorphous ferromagnetic layer of FeRh/CoFeB heterostructures. The MOKE and ferromagnetic resonance measurements show that the easy magnetization axes of the CoFeB layer are along the FeRh〈110〉 and FeRh〈100〉 directions for the epitaxially grown FeRh layer in the antiferromagnetic and ferromagnetic states, respectively. The combined Monte Carlo simulation and first-principles calculation indicate that the fourfold magnetic anisotropy of the amorphous CoFeB layer is imprinted due to the interfacial exchange coupling between the CoFeB and FeRh moments from the magnetocrystalline anisotropy of the epitaxial FeRh layer. This observation of imprinting the magnetocrystalline anisotropy of antiferromagnetic materials on easily detected ferromagnetic materials may be applied to probe the magnetic structures of antiferromagnetic materials without using synchrotron methods.Nanomagnets: Good impressions avoid need for X-raysCapturing magnetic structural information using nanoscale thin films can make it easier to spot materials that exploit the spin properties of electrons for use in spintronics devices. Most magnets have their electron spins aligned in one direction, but antiferromagnets have alternating up/down spins that are useful for sensors. Qingfeng Zhan from East China Normal University in Shanghai and Run-Wei Li at the Chinese Academy of Sciences in Ningbo and colleagues now report a method that identifies antiferromagnets without the use of high-powered X-ray equipment. The team demonstrated that alloys with amorphous crystal structures can convert into ordered frameworks with distinct spin patterns after being thinly coated onto an antiferromagnet’s surface. Using a combination of magnetometermicroscopy and computer simulations, the researchers showed that the antiferromagnet imprinted its magnetic ordering onto the alloy through quantum mechanical coupling effects.

We investigated the magnetic anisotropy and the high-frequency property of flexible Fe 60 Co 26 Ta 14 (FeCoTa) thin films obtained by oblique sputtering onto a wrinkled surface. The sinuously wrinkled topography is produced by growing Ta layer on a pre-strained polydimethylsiloxane (PDMS) membrane. Due to the enhanced effect of shadowing, the oblique deposition of FeCoTa layer gives rise to a shift of wrinkle peak towards the incident atomic flux. With increasing the PDMS pre-strain or increasing the oblique sputtering angle, both the uniaxial magnetic anisotropy and the ferromagnetic resonance frequency of FeCoTa films are enhanced, but the initial permeability decreases. The magnetization reversal mechanism of wrinkled FeCoTa films can be interpreted by a two-phase model composed of both coherent rotation and domain wall nucleation. With the enhancement of uniaxial magnetic anisotropy, the domain wall nucleation becomes pronounced in FeCoTa films.