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Metasurfaces have exhibited exceptional proficiency in precisely modulating light properties within narrow wavelength spectra. However, there is a growing demand for multi-resonant metasurfaces capable of wavefront engineering across broad spectral ranges. In this study, we introduce a microcavity-assisted multi-resonant metasurface platform that integrates subwavelength meta-atoms with a specially designed distributed Bragg reflector (DBR) substrate. This platform enables the simultaneous excitation of various resonant modes within the metasurface, resulting in multiple high- Q resonances spanning from the visible to the near-infrared (NIR) regions. The developed metasurface generates up to 15 high- Q resonant peaks across the visible-NIR spectrum, achieving a maximum efficiency of 81% (70.7%) in simulation (experiment) with an average efficiency of 76.6% (54.5%) and a standard deviation of 4.1% (11.1%). Additionally, we demonstrate the versatility of the multi-resonant metasurface in amplitude, phase, and wavefront modulations at peak wavelengths. By integrating structural color printing and vectorial holographic imaging, our proposed metasurface platform shows potential for applications in optical displays and encryption. This work paves the way for the development of next-generation multi-resonant metasurfaces with broad-ranging applications in photonics and beyond. Previous multi-wavelength metasurfaces are restricted to a few wavelengths or lack wavefront control ability. Here, the authors introduce a microcavity-assisted metasurface that achieves multi-resonant wavefront engineering at 15 high-Q peak wavelengths from 480 nm to 1000 nm.

Exceptional points (EPs) can achieve intriguing asymmetric control in non-Hermitian systems due to the degeneracy of eigenstates. Here, we present a general method that extends this specific asymmetric response of EP photonic systems to address any arbitrary fully-polarized light. By rotating the meta-structures at EP, Pancharatnam-Berry (PB) phase can be exclusively encoded on one of the circular polarization-conversion channels. To address any arbitrary wavefront, we superpose the optical signals originating from two orthogonally polarized -yet degenerate- EP eigenmodes. The construction of such orthogonal EP eigenstates pairs is achieved by applying mirror-symmetry to the nanostructure geometry flipping thereby the EP eigenmode handedness from left to right circular polarization. Non-Hermitian reflective PB metasurfaces designed using such EP superposition enable arbitrary, yet unidirectional, vectorial wavefront shaping devices. Our results open new avenues for topological wave control and illustrate the capabilities of topological photonics to distinctively operate on arbitrary polarization-state with enhanced performances. The authors report the chiral inversion of exceptional points (EPs) through a structural mirror-symmetric operation, extending the application of EP to any desired polarization states, surpassing the inherent limitation of conventional EP systems.

Exceptional points (EPs) are spectral singularities of non-Hermitian systems and represent the coalescence of eigenvalues and eigenstates. Traditional photonic systems typically exhibit coalesced eigenstates that correspond to circular polarizations of a specific handedness, thereby restricting their applicability to only the poles of the Poincaré sphere. Here, by judiciously combining optical anisotropy, chirality and non-Hermiticity of diffractive plasmonic metasurfaces with basis transformation, we achieve a continuum of EPs for which the corresponding coalesced eigenstates can access any point on the Poincaré sphere, greatly alleviating the strict requirement of approaching EP degeneracy. Our theoretical proposal and experimental implementation overcome the main practical limitation of EPs, extending the applicability of the topological phase to arbitrarily polarized state within the diffraction region. The emergence of these non-conventional EPs not only contributes to applications in wavefront engineering and optical multiplexing, but also brings in new fundamental properties of topological systems in general. Qin et al. realized a plasmonic exceptional point distribution that covers full Poincaré sphere based on extrinsic chirality and basis transformation, extending the application of singularity induced topological phase to arbitrary polarization states.

HighlightsA symbiotic host of porous graphite layer is designed as hybrid Li anode for Li ion intercalation and subsequent uniform plating.An ultrahigh plating reversibility of 99.5% is achieved in the carbonate electrolyte.An air-stable cathode prelithiation agent is introduced to provide extra Li source, resulting high energy density of the as-developed practical hybrid Li-ion/metal full cell.The energy density of commercial lithium (Li) ion batteries with graphite anode is reaching the limit. It is believed that directly utilizing Li metal as anode without a host could enhance the battery’s energy density to the maximum extent. However, the poor reversibility and infinite volume change of Li metal hinder the realistic implementation of Li metal in battery community. Herein, a commercially viable hybrid Li-ion/metal battery is realized by a coordinated strategy of symbiotic anode and prelithiated cathode. To be specific, a scalable template-removal method is developed to fabricate the porous graphite layer (PGL), which acts as a symbiotic host for Li ion intercalation and subsequent Li metal deposition due to the enhanced lithiophilicity and sufficient ion-conducting pathways. A continuous dissolution-deintercalation mechanism during delithiation process further ensures the elimination of dead Li. As a result, when the excess plating Li reaches 30%, the PGL could deliver an ultrahigh average Coulombic efficiency of 99.5% for 180 cycles with a capacity of 2.48 mAh cm−2 in traditional carbonate electrolyte. Meanwhile, an air-stable recrystallized lithium oxalate with high specific capacity (514.3 mAh g−1) and moderate operating potential (4.7–5.0 V) is introduced as a sacrificial cathode to compensate the initial loss and provide Li source for subsequent cycles. Based on the prelithiated cathode and initial Li-free symbiotic anode, under a practical-level 3 mAh capacity, the assembled hybrid Li-ion/metal full cell with a P/N ratio (capacity ratio of LiNi0.8Co0.1Mn0.1O2 to graphite) of 1.3 exhibits significantly improved capacity retention after 300 cycles, indicating its great potential for high-energy-density Li batteries.

Topological defects and disorder counteract each other 1 , 2 , 3 , 4 – 5 . Intuitively, disorder is considered detrimental, requiring efforts to mitigate its effects in conventional topological photonics 6 , 7 , 8 – 9 . We propose a counter-intuitive approach that exploits a real–momentum topological photonic crystal that harnesses real-space disorder to generate a Pancharatnam–Berry phase 10 , 11 , without disrupting the momentum-space singularity originating from bound states in the continuum 12 . This methodology allows flat optical devices to encode spatial information or even extra topological charge in real space while preserving the topology of bound states in the continuum in momentum space with inherent alignment. Here, as a proof of concept, we demonstrate the simultaneous and independent generation of a real-space broadband vortex or a holographic image alongside resonant momentum-space vortex beams with a narrow bandwidth, which cannot be achieved with conventional methods. Such engineered disorder contributes to vast intrinsic freedoms without adding extra dimensions or compromising the optical flatness 13 , 14 . Our findings of real–momentum duality not only lay the foundation for disorder engineering in topological photonics but also open new avenues for optical wavefront shaping, encryption and communications. A real–momentum topological photonic crystal that harnesses real-space disorder is used to generate a Pancharatnam–Berry phase while preserving momentum-space topology.

Lithium (Li) metal is the ultimate anode choice for next generation high energy density batteries. However, the high nucleation energy barrier and nonuniform electric field distribution, as well as huge volume expansion, lead to the uncontrollable growth of Li dendrites and poor utilization of Li metal, which hinders its practical application. Herein, titanium dioxide/cuprous oxide (TiO 2 /Cu 2 O) heterostructure is constructed on the rimous skeleton of Cu mesh, and the heterostructure decorated rimous Cu mesh (H-CM) can act as both current collector and host for dendrite-free Li metal anode. The TiO 2 /Cu 2 O heterostructure realizes selective Li nucleation by nano TiO 2 and then induces fast and uniform Li conduction with the aid of heterostructure interface and nano Cu 2 O contributing to dendrite-free Li deposition. While the internal and external space of rimous skeletons in H-CM is used to accommodate the deposited Li and buffer its volume change. Therefore, the cycling reversibility of the derived Li metal anode in H-CM is improved to a high Coulombic efficiency of 98.8% for more than 350 cycles at a current density of 1 mA·cm −2 , and 1,000 h (equals to 500 cycles) stable repeated Li plating/stripping can be operated in a symmetric cell. Furthermore, full cells with limited Li anode and high loading LiFePO 4 cathode present excellent cycling and rate performances.

Established by the Center for Mental Health Services (CMHS), the Comprehensive Community Mental Health Services for Children and Their Families Program is an innovative effort to establish systems of care in communities across the country. Using data from three participating sites, we examined service use and expenditures under systems of care.We found that sites provided children with a full range of mental health services. We also found that per-child expenditures were high, but for two of the sites, those expenditures were within the range of expenditures in other innovative attempts at service delivery. In one site, expenditures were especially high. One explanation is that individuals treated there had particularly severe problems, and the data confirmed this explanation, at least to some extent. In particular, when we limited the analyses to a comparable group of children with severe emotional disturbance, expenditures at that site were comparable to those from the Fort Bragg Demonstration.We also found that the sites were successful in developing alternative sources of funding over time. By the last year of the grant, CMHS funds represented no more than one fourth of project funds. This trend reflected program requirements and suggested that the sites developed fiscal sustainability over time.

The rapid advancement of image-generation technologies has made it possible for anyone to create photorealistic images using generative models, raising significant security concerns. To mitigate malicious use, tracing the origin of such images is essential. Reconstruction-based attribution methods offer a promising solution, but they often suffer from reduced accuracy and high computational costs when applied to state-of-the-art (SOTA) models. To address these challenges, we propose AEDR (AutoEncoder Double-Reconstruction), a novel training-free attribution method designed for generative models with continuous autoencoders. Unlike existing reconstruction-based approaches that rely on the value of a single reconstruction loss, AEDR performs two consecutive reconstructions using the model's autoencoder, and adopts the ratio of these two reconstruction losses as the attribution signal. This signal is further calibrated using the image homogeneity metric to improve accuracy, which inherently cancels out absolute biases caused by image complexity, with autoencoder-based reconstruction ensuring superior computational efficiency. Experiments on eight top latent diffusion models show that AEDR achieves 25.5% higher attribution accuracy than existing reconstruction-based methods, while requiring only 1% of the computational time.

The rapid advancement of image-generation technologies has made it possible for anyone to create photorealistic images using generative models, raising significant security concerns. To mitigate malicious use, tracing the origin of such images is essential. Reconstruction-based attribution methods offer a promising solution, but they often suffer from reduced accuracy and high computational costs when applied to state-of-the-art (SOTA) models. To address these challenges, we propose AEDR (AutoEncoder Double-Reconstruction), a novel training-free attribution method designed for generative models with continuous autoencoders. Unlike existing reconstruction-based approaches that rely on the value of a single reconstruction loss, AEDR performs two consecutive reconstructions using the model's autoencoder, and adopts the ratio of these two reconstruction losses as the attribution signal. This signal is further calibrated using the image homogeneity metric to improve accuracy, which inherently cancels out absolute biases caused by image complexity, with autoencoder-based reconstruction ensuring superior computational efficiency. Experiments on eight top latent diffusion models show that AEDR achieves 25.5% higher attribution accuracy than existing reconstruction-based methods, while requiring only 1% of the computational time.