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We apply ultrafast nanoscale microscopic imaging and analytical modeling to investigate the coherent field and spin textures of dual plasmonic vortices as a means to design the momentum flow, and spin topology by interaction of their gyrating fields. The ultrafast laser normal incidence illumination by circularly polarized light of two vortex generator structures with variable separations in silver films launches structured surface plasmon polariton fields. Two distinct primary vortices and a third emergent vortex, generated by interaction of the primary vortices and tunable by design of their separation, form through the spin–orbit interaction of light. The gyration of plasmon fields and the consequent vectorial Poynting momentum flow is imaged with sub-optical cycle phase and spatial resolution by interferometric time-resolved two-photon photoemission electron microscopy (ITR-2P-PEEM). The ultrafast imaging and analytical modeling of the interaction of the dual plasmonic vortices examines the nanoscale control of plasmon spin topology and momentum driven transport. 

The Cl–S mixed-anion sublattice of Li_1.6AlCl_3.4S_0.6creates face- and edge-shared octahedra that connect to form 3D ion conduction pathways with low activation energy barriers. 

Li_3.6In₇S_11.8Cl has a face-centered cubic arrangement of S²⁻/Cl⁻stabilized by Li⁺/In³⁺that form 3D ion conduction paths. The moisture stability and fast ion conduction make Li_3.6In₇S_11.8Cl a promising electrolyte for solid-state batteries. 

Abstract All‐solid‐state potassium batteries emerge as promising alternatives to lithium batteries, leveraging their high natural abundance and cost‐effectiveness. Developing potassium solid electrolytes (SEs) with high room‐temperature ionic conductivity is critical for realizing efficient potassium batteries. In this study, we present the synthesis of K_2.98Sb_0.91S_3.53Cl_0.47, showcasing a room‐temperature ionic conductivity of 0.32 mS/cm and a low activation energy of 0.26 eV. This represents an increase of over two orders of magnitude compared to the parent compound K₃SbS₄, marking the highest reported ionic conductivity for non‐oxide potassium SEs. Solid‐state³⁹K magic‐angle‐spinning nuclear magnetic resonance on K_2.98Sb_0.91S_3.53Cl_0.47reveals an increased population of mobile K⁺ions with fast dynamics. Ab initio molecular dynamics (AIMD) simulations further confirm a delocalized K⁺density and significantly enhanced K⁺diffusion. This work demonstrates diversification of the anion sublattice as an effective approach to enhance ion transport and highlights K_2.98Sb_0.91S_3.53Cl_0.47as a promising SE for all‐solid‐state potassium batteries. 

Abstract We report a theoretical investigation of effects of Mn and Co substitution in the transition metal sites of the kagomé-lattice ferromagnet, Fe₃Sn₂. Herein, hole- and electron-doping effects of Fe₃Sn₂have been studied by density-functional theory calculations on the parent phase and on the substituted structural models of Fe_3−xM_xSn₂(M = Mn, Co;x= 0.5, 1.0). All optimized structures favor the ferromagnetic ground state. Analysis of the electronic density of states (DOS) and band structure plots reveals that the hole (electron) doping leads to a progressive decrease (increase) in the magnetic moment per Fe atom and per unit cell overall. The high DOS is retained nearby the Fermi level in the case of both Mn and Co substitutions. The electron doping with Co results in the loss of nodal band degeneracies, while in the case of hole doping with Mn emergent nodal band degeneracies and flatbands initially are suppressed in Fe_2.5Mn_0.5Sn₂but re-emerge in Fe₂MnSn₂. These results provide key insights into potential modifications of intriguing coupling between electronic and spin degrees of freedom observed in Fe₃Sn₂. 

Habitat degradation and loss of genetic diversity are common threats faced by almost all of today’s wild cats. Big cats, such as tigers and lions, are of great concern and have received considerable conservation attention through policies and international actions. However, knowledge of and conservation actions for small wild cats are lagging considerably behind. The black-footed cat,Felis nigripes, one of the smallest felid species, is experiencing increasing threats with a rapid reduction in population size. However, there is a lack of genetic information to assist in developing effective conservation actions. A de novo assembly of a high-quality chromosome-level reference genome of the black-footed cat was made, and comparative genomics and population genomics analyses were carried out. These analyses revealed that the most significant genetic changes in the evolution of the black-footed cat are the rapid evolution of sensory and metabolic-related genes, reflecting genetic adaptations to its characteristic nocturnal hunting and a high metabolic rate. Genomes of the black-footed cat exhibit a high level of inbreeding, especially for signals of recent inbreeding events, which suggest that they may have experienced severe genetic isolation caused by habitat fragmentation. More importantly, inbreeding associated with two deleterious mutated genes may exacerbate the risk of amyloidosis, the dominant disease that causes mortality of about 70% of captive individuals. Our research provides comprehensive documentation of the evolutionary history of the black-footed cat and suggests that there is an urgent need to investigate genomic variations of small felids worldwide to support effective conservation actions.