Piezoelectric microelectromechanical systems (MEMS) have garnered considerable interest due to the incorporation of active piezoelectric layers, enabling integrated actuation, sensing, and transduction functionalities. Achieving high piezoelectric response in functional thin films grown on silicon-based substrates remains a critical challenge for realizing high-performance piezoelectric MEMS. In this work, high-quality <100>-oriented 0.26Pb(In1/2Nb1/2)O3-0.40(Mg1/2Nb2/3)O3-0.34PbTiO3 (PIMNT (26/40/34)) thin films were grown on the Pt/Ti/SiO2/Si substrates by sputtering. X-ray diffraction, scanning electron microscopy, and piezoresponse force microscopy were utilized, and thickness-dependent electrical properties were characterized. The optimized <100>-oriented films exhibited a dense microstructure and outstanding dielectric and piezoelectric performance, with a low-field relative dielectric constant of ∼ 2898 (tanδ ∼ 0.049) at 1 kHz and a remnant polarization of 38.2 μC/cm2. After upward DC poling, a high piezoelectric coefficient of 240 pC/N was achieved. These results highlight the potential of <100>-oriented PIMNT thin films as efficient functional layers for high-performance piezoelectric MEMS devices.

In this work, we aim to report a multifunctional organic fluorescent crystal - 2-(phenothiazine-10-yl)-anthraquinone (Pht-AQ), simultaneously possessing ferroelectric behavior, phosphorescence (PH) and aggregationinduced emission (AIE). Different from the common design approaches of symmetry breaking in organic ferroelectrics, here the spontaneous polarization of the crystal was achieved by a solvent molecule - dioxane, which formed co-crystal with the Pht-AQ during crystallization. The crystal showed a ferroelectric-paraelectric transition from P1 to P-1 space group at -7.7 degrees C, and polarization switching feature was observed by ferroelectric hysteresis loop and domain structure characterization. The AIE and PH properties which arise from the intrinsic donor-acceptor (D-A) structure of Pht-AQ is maintained in the crystal, while dioxane can undergo free rotation at high temperature or in the external electrical field, which endows the crystal with ferroelectric phase transition and polarization switching behavior. This work showed a possible strategy to achieve integration of multiphysical property in a single material by co-crystallization, which might pave the way for developing multifunctional ferroelectrics with unique opto-electrical properties.

Real-time navigation of nanorobots with high spatiotemporal resolution and molecular contrast in deep tissues via noninvasive manners has been challenging. Here, we developed near-infrared II (NIR-II; 1000 to 3000 nanometers) magnetic nanorobots that balance fluorescence brightness at ~1600 nanometers with magnetic strength, facilitating precise gathering or locomotion of the nanorobots in the peritoneal cavity, hindlimb, liver, spleen, and lower gastrointestinal tract of live mice under real-time NIR-II imaging guidance with high resolution and sensitivity. Two-plex NIR-II imaging enabled precise locomotion by simultaneously providing real-time information on both the location of nanorobots and the position of target sites with molecular specificity. NIR-II magnetic nanorobots remained stable in gastric juice simulated solution (pH = 2) for more than 2 weeks. The magnetic locomotion of nanorobots loaded with 5-aminosalicylic acid under NIR-II visual feedback enables targeted delivery to the lower gastrointestinal tract and effectively enhances therapeutic efficacy in mice with inflammatory bowel disease. This platform opens an avenue in precision medicine.

This study presents a high-performance surface acoustic wave (SAW) resonator-based filter using 42°YX LiTaO3/SiO2/α-Si/SiC multilayered substrate. The SAW resonator and filter were optimized using the finite element method (FEM), with a piston structure incorporated to enhance performance. The measured results show that the optimized resonator achieves an electromechanical coupling coefficient (k2) of 10.24% and a Q fact of 1875. SAW filter based on the proposed resonator demonstrates configurable fractional bandwidth (FBW) and out-of-band rejection (OoB), confirming its practical utility for radio frequency applications. This work provides an effective design strategy for developing high-performance surface acoustic wave filters with enhanced frequency stability for next-generation wireless systems.

Potassium niobate-based [(KNbO3)0.9(BaNi1/2Nb1/2O3-delta)0.1, abbreviated: KBNNO] ferroelectrics have recently triggered great attentions because of its unique advantages of stable structure, narrow-bandgap, good photovoltaic properties and environment-friendly composites. However, exploring new strategies to dynamically and reversibly regulate and enhance the photocurrent of KNbO3-based thin films is still of great significance. In this work, we propose to grow flexible KBNNO thin films on an inorganic Mica substrate. The integration of in-situ electric-field poling and the strain-gradient-induced flexoelectric field enables dynamic and reversible modulation of photocurrent, thereby boosting its output performance for ferroelectric photovoltaic applications. Under a single electric field polarization, the current increases from 8.09 & micro;A/cm2 to 10.72 & micro;A/cm2, and then to 12.10 & micro;A/ cm2 with the synergy of the flexoelectric effect. This work opens a promising path for the development of multifunctional flexible optoelectronic materials.

Fiber-bundle endoscopy offers a compact and flexible route for clinical fluorescence imaging through natural human orifices, but since its first report in the 1950s, it has remained limited by low spatial resolution, honeycomb artifacts, and inter-core crosstalk. The crosstalk becomes more pronounced at near-infrared-II wavelengths (NIR-II, 1000-3000 nm), a spectral window that offers superior contrast, resolution, and tissue penetration depth for biomedical imaging. Here, we present an AI-powered flexible endoscopy platform that overcomes these constraints through optical-computational co-design: optimizing ultrathin fiber bundles to mitigate crosstalk-induced image blur and enable high-fidelity image transmission across the visible-to-NIR-II spectral range, and developing an Agent-Guided Mixture-of-Experts (GAME) pipeline for honeycomb-artifact removal and image restoration. GAME provides a single restoration entry point for diverse biomedical images acquired with our endoscope, spanning cell, mouse and human samples. It dynamically routes each input to suitable restoration experts via a vision-language model, facilitating image reconstruction with a fourfold resolution improvement beyond the NyquistShannon sampling limit. The utility of our endoscope is demonstrated through in vivo NIR-II imaging of anatomical structures in mice, as well as imaging of the digital micromirror device (DMD)-projected human gastric tube and lymphatic system, paving the way for future clinical translation.

Aqueous zinc-iodine (Zn-I2) batteries are promising candidates for safe and cost-effective energy storage, yet their practical application is limited by uncontrolled iodine speciation at electrified interfaces, driving severe polyiodide shuttling and parasitic reactions that cause rapid capacity fading. Existing strategies predominantly rely on static confinement or adsorption, which cannot adapt to evolving iodine speciation during charge-discharge, causing a trade-off between shuttle suppression and redox kinetics. In this study, we report a proton-switching strategy that regulates interfacial iodine chemistry via electrochemically driven protonation-deprotonation within an imine-linked two-dimensional polymer framework, thereby dynamically rewiring interfacial electrostatics during cycling. During discharge, protonation of imine generates positively polarized C═NH+ sites that stabilize I- through electrostatic interactions, enabling controlled reduction of polyiodides without accumulation. Upon charging, deprotonation restores the neutral framework, favoring polyiodide stabilization and efficient iodine oxidation. As a result, the constructed Zn-I2 battery delivers 51 000 cycles at 20 A g-1 at 25°C and sustains over 70 000 cycles at -20°C. This durability is retained at a high iodine loading of 35.7 mg cm-2, delivering an areal capacity of 5 mAh cm-2 over 2000 cycles with negligible decay, placing this system among the most durable Zn-I2 batteries.

Elasticity has long been regarded as a property exclusive to material media. Here we uncover its hidden existence in the spin degree of freedom. We introduce spin elasticity-an intrinsic mechanism that governs recoverable deformation of spin morphology. This discovery reveals a previously unrecognized universality: elasticity operates in both matter and spin spaces, underpinning structural integrity across physical realms. By establishing the missing spin counterpart, this work completes the elastic picture and points toward a broader paradigm where elasticity transcends its conventional boundaries.

ABSTRACT To develop high‐performance materials for infrared detection and energy harvesting applications, the pyroelectric properties and thermal stability of [001]‐oriented 0.5 mol% Mn‐doped 0.63Pb(Mg 1/3 Nb 2/3 )O 3 ‐0.37PbTiO 3 tetragonal single crystals were investigated. At room temperature, the crystals exhibit a high pyroelectric coefficient ( p ) of 7.9 × 10 −4 C m −2 K −1 , suppressed dielectric permittivity ( ε r ) of 578, and dielectric loss (tan δ ) of 0.0013, which is reduced by approximately 68% at 100 Hz by Mn‐doping. Furthermore, the values of ε r and tan δ remain low for thermal treatment temperatures below 90°C, indicating only slight depolarization in crystals. The high p and suppression of dielectric properties lead to high figures of merit for current responsivity F i = 3.2 × 10 −10 m V −1 , voltage responsivity F v = 0.06 m 2 C −1 , detectivity F d = 12.3 × 10 −5 Pa −1/2 , and energy harvesting F E = 122.0 × 10 −11 J m −3 K −2 at 100 Hz. As the temperature increases to 90°C, the values of F i , F v , F d , and F E remain 111%, 84%, 70%, and 94% of their room‐temperature values, respectively, due to its high Curie temperature of 172°C. The high pyroelectric properties and superior thermal stability make the crystals promising for high‐performance and wide‐operational‐temperature infrared detectors and energy harvesters.

Piezoelectric micromachined ultrasonic transducers (pMUTs) hold great promise for applications ranging from medical imaging to range finding, yet their widespread adoption is hindered by low transmitting sensitivity. To address this limitation, we introduce a metasurface-integrated pMUT featuring a grooved hub-and-spoke structure, fabricated on an SiO2/Pt/PZT/Pt/SiO2/Si multilayer stack. In this design, the SiO2 vibration layer is strategically deposited above a patterned lead zirconate titanate (PZT) thin film with the precisely microfabricated geometry, a configuration that simultaneously enhances energy transduction and mitigates stress-induced performance deterioration. Experimental measurements validate the efficacy of the design, showing an increase in the electromechanical coupling coefficient from 0.68% to 2.95%. The device achieves a transmitting sensitivity of 0.71 Pa/V at 10 cm, representing a 2.36-fold improvement over conventional designs. Furthermore, the integrated stress-relieving grooves ensure exceptional wafer-scale uniformity, confining resonant frequency deviations to within 4% across an 8-in. wafer. These results, combined with a silicon-based CMOS-compatible fabrication process that emphasizes simplicity and cost-effectiveness, establish the proposed meta-pMUT as a highly viable and competitive technology for the commercialization of next-generation ultrasonic systems.

Abstract Light scattering in scintillators is a pervasive problem and a key factor limiting X-ray imaging resolution. Here, we shift scintillator radioluminescence from the traditional visible range into the short-wave infrared (SWIR) or near-infrared II (NIR-II, 1000-3000 nm) window to mitigate light scattering and thereby enhance light penetration and X-ray imaging resolution. We present an NIR-II MgGa 2 O 4 :Ni 2+ scintillator with peak emission at 1340 nm, achieving a threefold improvement in X-ray imaging resolution compared with visible scintillators owing to reduced light scattering. This heavy-metal-free NIR-II scintillator exhibits intense radioluminescence comparable to that of conventional visible-emitting CsI:Tl, achieving a detection limit of 56 nanograys per second, ∼100-fold lower than typical doses used in medical imaging. We show that this NIR-II scintillator enables high-resolution X-ray radiography of electronic circuit boards and biological tissues.

This work systematically investigates the third-order harmonic nonlinearity of surface acoustic wave (SAW) resonators by integrating the finite element method (FEM) with perturbation theory. First, the third-harmonic (H3) nonlinear signals in 42°YX–LiTaO3 based SAW resonator was simulated using a nonlinear FEM model. This model was validated by comparison of the simulated H3 to that of the experimental results. The simulated and measured results exhibit excellent agreement in both amplitude and phase of H3, demonstrating the capability of phase analysis. Furthermore, contributions of the six independent strain components to the H3 response were individually calculated and analyzed, showing that the Syz component dominates both the amplitude and phase responses in the overall H3 behavior. This work provides valuable insights for the design of high-performance SAW devices in radio-frequency front-end circuits and potential applications for nonlinear suppression through phase-based optimization.

Ferroelectric topological vortex domains have attracted interest for their topologically protected properties and potential in next-generation electronics. Although extensive research has focused on low-dimensional nanostructures, the role of vortex domains in bulk ferroelectrics remains poorly understood. Here we identify topological vortex structures in bulk Pb(Mg1/3Nb2/3)O3-PbTiO3 crystals and demonstrate their direct role in enhancing the piezoelectric response, establishing a mechanistic link between vortex structures and macroscopic performance. We develop a straightforward and scalable method, mechanically assisted electrical poling, to engineer vortex domain density, which increases the vortex core density from 0.01 μm-2 in conventionally poled samples to 21 μm-2. This controlled domain engineering leads to a remarkable improvement in the piezoelectric response, primarily attributed to localized strain surrounding the vortex cores. This study advances our understanding of topological structures in bulk ferroelectrics, and opens up a practical pathway to engineer high-performance ferroelectrics for device applications.

This letter presents a high-performance wide-band surface acoustic wave (SAW) filter using a parallel longitudinally coupled double-mode SAW (DMS) structure on LiTaO3/SiO2/alpha-Si/Si multilayer substrate. The proposed DMS filter, designed and optimized using the finite element method (FEM), successfully achieves a combined passband with twice the bandwidth of a conventional single DMS filter. Experimental results demonstrate a fractional bandwidth (FBW) of 12.6%, confirming its enhanced broadband performance. Moreover, it exhibits temperature coefficients of frequency as low as 3.17 ppm/degrees C at the upper sidebands within the-3 dB bandwidth, together with a power handling capability of 25.5 dBm, indicating good temperature stability and high power durability. These superior characteristics make the proposed filter a promising candidate for next-generation radio frequency (RF) front-end systems.

The accurate quantification of α-glucosidase (α-Glu) activity and its inhibitor is of vital for diabetes diagnosis and drug screening. Enzyme activity could be detected by developing a sensing method based on nanozyme-involved cascade reaction. However, such a cascade reaction typically produces only one signal, whereas the fabrication of multifunctional nanozymes toward this end remains a formidable challenge. Herein, iron-doped fluorescent polymer dots (Fe-PDs) were one-pot synthesized under mild conditions. Iron doping accelerates PDs formation and imparts prominent peroxidase (POD)-like activity to the material. The as-prepared Fe-PDs could catalyze the oxidation of colorless TMB by H2O2 to form chromogenic oxTMB, which quenched the intrinsic fluorescence of Fe-PDs via the inner filter effect (IFE). Relying on three-catalyst cascade catalysis of α-Glu, glucose oxidase (GOx) and POD, this work constructed a highly sensitive colorimetric-fluorescent sensing platform. By introducing p-nitrophenyl-α-D-glucopyranoside (PNPG) as the substrate, the system enables quantitative analysis of H2O2, glucose, α-Glu activity as well as α-Glu inhibitors. Benefiting from cascade-induced signal amplification, the dual-modal assay enables quantitative analysis of α-Glu activity with linear ranges of 0.2-20 mU/mL (colorimetry) and 0.2-25 mU/mL (fluorometry), and detection limits of 0.10 and 0.094 mU/mL, respectively. Furthermore, this assay enables the screening of α-Glu inhibitors (AGIs) and determination of AGIs in real samples, which shows satisfactory consistency compared with the traditional PNPG assay, demonstrating the great application prospects for clinical diagnosis and anti-diabetic drug discovery.

Elasticity shapes our world. For centuries, it has been regarded as a property exclusive to ordinary matter. Here we uncover its hidden existence in the spin degree of freedom. We introduce spin elasticity-a framework linking spin torque to spin morpgology. This reveals a topological Hooke's law, uncovers spontaneous oscillations and resonance, and predicts a new class of collective excitations:spin stress waves. By establishing a unfied tau-D theory bridging classical elasticity and topological spin physics, this work completes the elastic picture and opens a new frontier for spintronics-spinelastronics.

Strong adhesion between the hole transport layer and transparent conductive oxide is crucial for efficient charge transport and interface stability of inverted perovskite solar cells (PSCs). This study demonstrates a significant improvement in interface adhesion achieved through rational hole transporter design. We design poly-DCPA, a novel polymeric hole transporter exhibiting over four-fold enhancement in adhesion compared to the self-assembled monolayer (SAM) counterpart called DCPA. Poly-DCPA also shows superior conductivity and improved uniformity, enabling blade-coated PSCs fabricated under ambient conditions to achieve a remarkable power conversion efficiency of 24.9%. This surpasses the performance of PSCs using the DCPA SAM as the hole-transporting layer. Furthermore, poly-DCPA-based PSCs exhibit excellent stability, retaining 94% of the initial PCE after over 900 hours of light soaking at 85 degrees C. This work presents a promising strategy for designing hole transporters with enhanced interface adhesion, paving the way for highly efficient and stable PSCs.

Reverse bias stability remains a critical challenge for inverted perovskite solar cells (PSCs). While self-assembled monolayers (SAMs) boost efficiency, their low breakdown voltages limit device reliability. Thick PTAA layer improves breakdown voltage but suffers from poor wettability and efficiency loss, with unclear effects on device reverse bias stability. Here, we use electroluminescence mapping to reveal the critical role of hole transport layer (HTL) uniformity in affecting device reverse bias stability, and poor uniformity of current HTLs causes spatial heterogeneity that is not able to block electron injection and leads to device breakdown under reverse bias. Based on our study, we develop a polymeric Poly-PhPACz HTL with high conductivity and good wettability, achieving a breakdown voltage comparable to PTAA while maintaining high efficiencies across varying thicknesses. Ambient blade-coated Poly-PhPACz PSCs achieve 26.1% efficiency and retain 92% performance after 1,800 hours of light soaking. Further optimization yields a high breakdown voltage of -14.3 V without sacrificing efficiency, offering a promising pathway for stable PSCs.

Rechargeable Na/Cl2 batteries were developed for the first time using multiwalled carbon nanotube (MWCNT) positive electrodes in SOCl2-based electrolytes. At room temperature, these batteries delivered high cycling specific capacities up to 3500 mA h g-1 (normalized to CNT mass) with ∼3.9 V discharge voltage at up to 2 C rates over >140 cycles. In situ Raman spectroscopy experiments combined with real-time optical microscopy imaging revealed reversible formation and reduction of SCl2 and S2Cl2 species during battery operation, responsible for the additional plateaus to the main Cl-/Cl2 redox reactions. Cryo-TEM revealed NaCl nanocrystals inside the hollow inner space of CNTs through battery cycling, suggesting Cl-/Cl2 redox reactions reaching hollow CNTs likely through defects and open ends on MWCNTs. High-resolution electron energy loss spectroscopy (EELS) mapping revealed Cl uniformly distributed along CNTs in the charged state, suggesting CNTs as a novel carbon material to host Cl-/Cl2 redox and store chlorine for reversible conversion between NaCl and Cl2 and battery rechargeability.

Several advanced techniques have been used for 3D micro-surface profiling, such as white light interferometry, confocal microscopy, and atomic force microscopy. However, a major technological limitation shared among these methods is the difficulty of imaging dynamic samples in real-time at high resolution. Specifically, profiling rapidly changing or moving surfaces at nanoscale 3D spatial resolution remains a challenging task. We demonstrate here a high-speed MEMS mirror-based laser differential confocal microscope for dynamic 3D micro-surface profiling. The MEMS mirror enables 2D scanning of 1200 × 650 pixels with a 140 × 90 μm field of view at 80 frames per second. Using laser differential confocal detection, the system achieves 25 nm axial resolution. The objective-space telecentric laser projection results in uniform axial response across the field of view, simplifying data acquisition and processing. These capabilities enable real-time 3D micro/nano scale profiling of dynamically changing surfaces at 80 frames per second without requiring motion stages. The system's substantial increase in imaging throughput enables, for the first time, real-time 3D profiling of dynamic microscale surface topographies at nanometer-level axial resolutions. The high-speed 3D profiling enabled by this system provides new insights for process development and quality control in precision micro/nano fabrication.