查看更多>>摘要：Edge detection is a fundamental operation for feature extraction in image processing.The all-optical method has aroused growing interest owing to its ultra-fast speed,low energy consumption and parallel computation.However,current optical edge detection methods are generally limited to static devices and fixed functionality.Herein,we propose a fast-switchable scheme based on a ferroelectric liquid crystal topological structure.The self-assembled chiral lamellar superstructure,directed by the azimuthally variant photo-alignment agent,can be dynamically controlled by the polarity of the external electric field and respectively generates the vector beams with nearly orthogonal polarization distribution.Even after thousands of cycles,the horizontal and vertical edges of the object are selectively enhanced with an ultra-fast switching time of～57 μs.Broadband edge-enhanced imaging is efficiently demonstrated.This work extends the ingenious building of topological heliconical superstructures and offers an important glimpse into their potential in the emerging frontiers of optical computing for artificial intelligence.
查看更多>>摘要：High magnetic fields play a crucial role in advancing basic sciences,fusion energy,and magnetic resonance imaging systems.However,the widespread use of high-field magnets requires affordable high-temperature superconducting wires that can carry large supercurrents.Iron-based superconductors offer an economically attractive solution to push forward important yet costly scientific programs,such as nuclear fusion reactors and next-generation particle accelerators.In this review,we start with the fabrication of iron-based superconducting wires and tapes and continue to discuss several key factors governing the current transport properties.State-of-the-art wires and tapes are introduced with emphasis on grain boundary characteristics,flux pinning,and anisotropy.The architecture of flexible conductors enables low cost,high mechanical strength,and high thermal stability.Recent progress in practical applications,including superconducting joints and insert coils,is also reviewed.Finally,we propose several key questions faced by iron-based superconductors in future practical applications.
查看更多>>摘要：An in-depth understanding of electrocatalytic mechanisms is essential for advancing electrocatalysts for the oxygen evolution reaction(OER).The emerging oxide pathway mechanism(OPM)streamlines direct O-O radical coupling,circumventing the formation of oxygen vacancy defects featured in the lattice oxygen mechanism(LOM)and bypassing additional reaction intermediates(*OOH)inherent to the adsorbate evolution mechanism(AEM).With only*O and*OH as intermediates,OPM-driven electrocatalysts stand out for their ability to disrupt traditional scaling relationships while ensuring stability.This review compiles the latest significant advances in OPM-based electrocatalysis,detailing design principles,synthetic methods,and sophisticated techniques to identify active sites and pathways.We conclude with prospective challenges and opportunities for OPM-driven electrocatalysts,aiming to advance the field into a new era by overcoming traditional constraints.
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