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Abstract Sequential infiltration synthesis (SIS) has emerged as a powerful technique to integrate inorganic materials into polymeric templates for fabricating functional hybrid and inorganic-only nanostructures. While several polymers, including self-assembled block copolymers (BCPs), have been widely used as templates for inorganic and hybrid oxide nanostructures, biocompatible polymers such as polycaprolactone (PCL) have not been explored for nanopatterning. In this work, we investigate SIS in polystyrene-block-polycaprolactone (PS-b-PCL) BCPs to demonstrate the feasibility of PCL as a guiding polymer for selective infiltration of Al₂O₃. Fourier transform infrared spectroscopy (FTIR) confirmed the strong interaction of TMA–H₂O precursors with the oxygen-containing functional groups of PCL, while scanning electron microscopy (SEM) revealed well-defined Al₂O₃ nanostructures after SIS and polymer removal. By varying the number of SIS cycles and processing temperatures, we observed systematic changes in the inorganic content and nanostructural fidelity, highlighting the tunability of the process. Notably, significant Al₂O₃ incorporation occurred during the first SIS cycle due to strong PCL–precursor interactions, even at temperatures as low as 60 °C, making the process both cost-effective and precise. These findings demonstrate that PCL is a promising guiding polymer for SIS, with potential to extend beyond conventional systems such as polymethylmethacrylate (PMMA). This work opens new opportunities for fabricating oxide nanostructures with applications in nanopatterning, dielectric coatings, and bio-related nanomaterials. 

Abstract Nature provides many examples of the benefits of nanoscopic surface structures in areas of adhesion and antifouling. Herein, the design, fabrication, and characterization of liquid crystal elastomer (LCE) films are presented with nanowire surface structures that exhibit tunable stimuli‐responsive deformations and enhanced adhesion properties. The LCE films are shown to curl toward the side with the nanowires when stimulated by heat or organic solvent vapors. In contrast, when a droplet of the same solvent is placed on the film, it curls away from the nanowire side due to nanowire‐induced capillary forces that cause unequal swelling. This characteristic curling deformation is shown to be reversible and can be optimized to match curved substrates, maximizing adhesive shear forces. By using chemical modification, the LCE nanowire films can be given underwater superoleophobicity, enabling oil repellency under a range of harsh conditions. This is combined with the nanowire‐induced frictional asymmetry and the reversible shape deformation to create an underwater droplet mixing robot, capable of performing chemical reactions in aqueous environments. These findings demonstrate the potential of nanowire‐augmented LCE films for advanced applications in soft robotics, adaptive adhesion, and easy chemical modification, with implications for designing responsive materials that integrate mechanical flexibility with surface functionality. 

Resonant excitation of high-index dielectric nanostructures and their coupling with molecular excitons provide great opportunities for engineering adaptable platforms for hybrid functional optical devices. Here, we numerically calculate resonance coupling of nonradiating anapole states to molecular excitons within silicon nanosphere-J-aggregate heterostructures under illumination with radially polarized cylindrical vector beams. The results show that the resonance coupling is accompanied by a scattering peak around the exciton transition frequency, and the anapole state splits into a pair of anticrossing eigenmodes with a mode splitting energy of ≈200meV. We also investigate the resonance coupling as a function of the J-aggregate parameters, such as thickness, exciton transition linewidth, and oscillator strength. Resonant coupling of the anapole states and J-aggregate heterostructures could be a promising platform for future nanophotonic applications such as in information processing and sensing. 

Abstract Nonradiating optical anapoles are special configurations of charge‐current distributions that do not radiate. It was theoretically predicted that, for microspheres, electric and magnetic dipolar coefficients can simultaneously vanish by engineering the incident light, leading to the excitation of nonradiatinghybridoptical anapoles. In this work, the experimental detection of hybrid optical anapoles in dielectric microspheres (TiO₂) is reported using dual detection optical spectroscopy, developed to enable sequential measurement of forward and backward scattering under tightly‐focused Gaussian beam (TFGB) illumination. The results show that the excitation of TiO₂microspheres (diameter,d≈1 µm) under TFGB illumination leads to the appearance of scattering minima in both the forward and backward directions within specific wavelength ranges. These scattering minima are found to be due to vanishing electric and magnetic dipolar coefficients associated with hybrid optical anapoles. The ability to confine electromagnetic fields associated with hybrid optical anapoles can give rise to several novel optical phenomena and applications.