Physics

The strongly correlated oxides with a honeycomb lattice have attracted vast attention due to their interesting magnetic behaviors and emergent quantum effects such as Majorana fermions generated from Kitaev spin liquid. High-quality single crystal samples with delicately controlled composition and strain are highly required in this area. In this work, honeycomb structure built by edge-sharing ${\mathrm{CoO}}_{6}$ octahedra is stabilized in ilmenite matrix by doping 4% Co into ${\mathrm{NaSbO}}_{3}$. By performing magnetic measurements and first principles calculations, it is suggested that honeycomb local motifs containing ${\mathrm{Co}}^{2+}$ $(3{d}^{7})$ cobalt may exist in Co-doped ${\mathrm{NaSbO}}_{3}$ thin films, and exhibit ferromagnetic-like transition at \ensuremath{\sim}88 K. Meanwhile, the interlayer dipolar interaction may lead to antiferromagnetic coupling between the nearest layers. This work reveals the possibility to embed $3{d}^{7}$ honeycomb structure into an ilmenite matrix and provides a platform for future spin liquid exploration as well as quantum information technology.

Inducing magnetism in d 0 nonmagnetic oxides is a central challenge in condensed matter physics and a bottleneck for developing advanced spintronic devices. KTaO 3 epitomizes this challenge: Despite having strong spin-orbit coupling, its functionality is hindered by a stable nonmagnetic cubic phase. Here, we report the unlocking of magnetism in KTaO 3 via supercritical carbon dioxide (SC CO 2 ), which induces a stable monoclinic phase that has, until now, remained undiscovered. Experimentally, we demonstrate that this monoclinic phase has spontaneous magnetic moments, driving the system into a spin-glass state. Monte Carlo simulations pinpoint the origin of this glassy behavior to interfacial phase frustration, arising from the coupling between ferromagnetic facets and an antiferromagnetic bulk. To our knowledge, this work not only presents the first observation of a magnetic phase in KTaO 3 but also reveals a peculiar phenomenon of SC CO 2 –induced interfacial phase frustration, establishing a versatile strategy for engineering complex magnetic states in quantum paraelectric.

How do magnetic fields shape the way young stars gather gas from their birth clouds? Using high-resolution Atacama Large Millimeter/submillimeter Array observations of a young triple protostellar system HOPS-182, we identify an elongated stream of gas, or accretion streamer, that extends over several thousand astronomical units (1 astronomical unit is the Earth-Sun distance) and carries a substantial flow of material toward the system. The gas speeds along this filament increase toward the star in a way consistent with gravitational free fall, while the streamer's shape closely follows the magnetic field threading the region. By comparing the strengths of gravity and magnetic tension and measuring how the gas rotates compared with the local magnetic field, we show that the field is strong enough to help confine and guide the infalling gas and efficiently remove the angular momentum. These results suggest that a substantial fraction of the material falling onto young protostellar systems can be funneled through elongated, magnetically structured accretion streamers.

A deeper understanding of room temperature polariton condensed phases is essential for advancing quantum applications. Spin degrees of freedom inherent in polariton particles manifest themselves in the form of spinor condensation, which has been demonstrated only at cryogenic temperatures in the past. Herein, we demonstrate room-temperature spinor polariton condensation in a lead-halide perovskite microcavity under nonresonant optical excitation. The crystalline anisotropy of the perovskite induces a linear polarization splitting of the lower polariton modes, and, above the condensation threshold, nonlinear polariton-polariton interactions drive the formation of elliptically polarized condensates. The condensation dynamics are analyzed using a spin-dependent Gross-Pitaevskii model, which provides a qualitative framework for understanding the experimentally observed polarization evolution and two-stage threshold behavior. Our findings pave the way for all-optical control of polariton spin states at room temperature, opening a path toward scalable polaritonic quantum devices.

The rapid growth of modern electronics has intensified concerns about electronic waste management at the end of a product’s life. Integrating closed-loop recyclability, where electronic materials can be efficiently recovered, reprocessed, and reused in regenerated products, is essential for achieving sustainable development, minimizing environmental impact, and realizing long-term economic benefits. However, achieving closed-loop recycling remains particularly challenging for complex electronic materials. Here, we demonstrate the closed-loop recycling of emerging multifunctional two-dimensional conjugated metal-organic frameworks (2D c -MOFs) through a mechanochemistry-induced on-demand degradation strategy. Exemplified with 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP)–based 2D c -MOFs, we show that ultrasonic cavitation facilitates selective cleavage of metal-ligand linkages in alkaline solutions enabling rapid material degradation (up to 92.4% within 30 min). The HHTP monomers are subsequently recovered with high purity and yield (96.3%), and reused to regenerate 2D c -MOFs, establishing a complete circular material life cycle. Our cradle-to-cradle life-cycle assessment reveals that, compared with direct synthesis, this closed-loop recycling approach substantially reduces both total energy consumption (52 versus 358 MJ kg −1 ) and greenhouse gas (CO 2 ) emission (4.8 versus 27.4 kg CO 2 -equiv), thereby substantially lowering the overall environmental impact relative to conventional electronic materials. Moreover, we demonstrate the practical utility of these recyclable 2D c -MOFs in several applications, including hydrogen gas sensors, supercapacitor electrodes, and degradable printed electronic devices. These results highlight the potential of 2D c -MOFs to advance circular electronics, laying the groundwork for a sustainable transformation within the electronics industry.

High quality factor and sensitivity are critical to wireless sensors targeting small perturbation detection. Although introducing parity-time symmetric dynamics promises enhanced performance, the symmetric scheme often yields limited sensing behaviors. In particular, its implementation is hindered by the inherent difficulties in decoupling capacitance- and coupling strength–induced responses, the requirements of delicately matching and/or tuning both gain and loss, and the need of strong coupling strength. Here, we report a concept of critical point (CP)–based wireless sensors that do not rely on balanced gain-loss configurations, delivering ultrahigh quality factor with an extended interrogation distance. Owing to a sharp and deep reflection dip, the CP-based scheme can resolve the change in coupling coefficient down to 1.92 × 10 −4 and features frequency-independent responses. Furthermore, the CP-based scheme allows for identification of tiny asymmetric capacitive perturbations as small as 2.5 × 10 −5 without requiring active tuning of the other parameters under weak coupling.

The hydrogen evolution reaction fundamentally constrains the use of aluminum in acidic electrochemical systems. Existing strategies rely on alloying or interfacial passivation and overlook how the electrolyte controls proton transport (PT) to the metal surface. Here, we demonstrate that the Gutmann donor number (DN) provides a quantitative molecular lever to regulate PT through the aqueous medium and suppress hydrogen evolution corrosion of aluminum. High-DN additives reorganize the electrolyte into compartmentalized domains that disrupt long-range PT and force protons onto tortuous, high-barrier pathways. Using water (DN = 18 kilocalories per mole) as a benchmark, additives exceeding this threshold increase the hydrogen evolution overpotential by ~20 to 70 millivolts at 10 milliamperes per square centimeter and reduce the corrosion current density from 7.44 to 2.23 milliamperes per square centimeter, following an approximately inverse linear dependence on DN. These results establish a direct link between a molecular donor descriptor and mesoscale hydrogen-bond networks, revealing a materials-agnostic strategy for corrosion suppression through targeted control of proton dynamics.

ABSTRACT Vacuum‐based deposition of hybrid organic–inorganic perovskites (HOIPs) remains a critical yet unresolved challenge for enabling scalable, solvent‐free manufacturing of perovskite optoelectronics. Here, tetragonal methylammonium lead iodide ( β ‐MAPbI 3 ) single‐phase crystals with high structural uniformity are synthesized via an antisolvent vapor‐assisted crystallization process and utilized as feedstock for a 3‐inch unsintered MAPbI 3 sputtering target fabricated through mechanochemical processing and low‐temperature consolidation. The resulting target exhibits sufficient compactness and mechanical integrity to sustain RF magnetron sputtering without macroscopic fracture while retaining its β ‐phase crystallographic signature under plasma exposure. However, sputtered films derived from this target consistently exhibit PbI 2 ‐dominant characteristics. Correlative analysis of target surface evolution and film composition indicates a progressive loss of organic and iodine species during sputtering, leading to a compositionally altered sputtered flux. Such behavior can be reasonably attributed to the combined effects of energetic ion bombardment and photon irradiation intrinsic to RF plasma environments. Consequently, direct sputter deposition does not readily preserve MAPbI 3 stoichiometry, even when high‐quality single‐phase crystal‐derived targets are employed, suggesting that post‐deposition reconstruction strategies may be required to restore the perovskite phase. This work provides fundamental insights into plasma–perovskite interactions and establishes a foundation for sputtering‐based routes toward scalable perovskite photoabsorber fabrication.

Abstract The development of future crystalline silicon (c‐Si) solar cell technologies requires innovative surface passivation layers. Sulfides are a somewhat unexplored class of passivation materials, despite previous reports showing that sulfurization of the c‐Si surface enhances surface passivation. Herein, we report a novel transparent passivation stack composed of ZnS/Al 2 O 3 , sequentially deposited by atomic layer deposition (ALD). This stack exhibits remarkable surface passivation, reaching a recombination current pre‐factor J 0 as low as 1.0 fA/cm 2 and implied open‐circuit voltages i V oc > 730 mV for a wide range of deposition and annealing conditions. Capacitance–voltage measurements reveal an extremely low interface state density of ≈ 1×10 10 cm −2 eV −1 , on par with state‐of‐the‐art Si‐based passivation layers such as SiO 2 and a‐Si:H, together with a moderate positive fixed charge. A close lattice match between c‐Si and ZnS suggests potential epitaxial growth, which could explain the low interface state density and outstanding surface passivation, despite the observation of a polycrystalline bulk structure. These results establish ZnS as an important new material for c‐Si surface passivation, with the potential to enable future innovations either as an interlayer for passivating contacts or as a dielectric passivation layer in c‐Si solar cells.

ABSTRACT Decoding the hidden scientific principles in massive and complex data causes bottlenecks in experimental science. A typical objective is to analyze the causes of battery aging through the local geometric environment. Here, we deployed visually aware virtual probes to see the hidden chemical fingerprints in active particles, decoding invisible stochastic microscopic events into visualized ensemble quantization behavior. By developing a deep learning architecture with hierarchical interaction perception, we break the detection bottleneck triggered by crack scale variability and decipher the multiscale aging code of massive particle microregions. The significant geometric mismatch effects in chemical microregions drive the Li + cross‐phase transport traps. This behavior leads to elevated contact stress, which ignites a degradation cascade reaction in batteries. Further, the electrode was reprogrammed according to the electrode microarchitecture engineering, extending the pouch cell life by 25%. Our approach, utilizing computer vision to analyze the hidden scientific laws behind the phenomena, guides the design of failure immunity in other energy systems.

ABSTRACT Conventional phosphonic acid‐based SAMs, exemplified by [4‐(3,6‐dimethoxy‐9H‐carbazol‐9‐yl)butyl]phosphonic acid (MeO‐4PACz), readily aggregate, leading to non‐uniform buried‐interface coverage and constrained device output. Here, we engineer co‐assembled SAMs (Co‐SAMs) by co‐assembling MeO‐4PACz with trimethoxysilane‐anchored terminal siloxanes—epoxy (GOPS), thiol (TMSPT) and isocyanate (IPTMS)—to homogenize the NiO x /perovskite contact. The resulting Co‐SAMs form denser and more uniform interfacial layers on NiO x , boosting the open‐circuit voltage ( V oc ) and fill factor (FF) of 1.68 eV wide‐bandgap perovskite solar cells, with IPTMS‐based Co‐SAMs delivering the largest improvement. Performance correlates with a distinct evolution of siloxane‐mediated intermolecular interactions. We demonstrate that the evolution of intermolecular interactions from physical blending (MeO4‐GOPS) and specific hydrogen bonding (MeO4‐TMSPT) to covalent bridging (MeO4‐IPTMS) significantly enhances interfacial quality. Specifically, the phosphonate–carbamate covalent bridge formed in MeO4‐IPTMS most effectively suppresses aggregation and delivers synergistic defect passivation. Leveraging this strategy, monolithic perovskite/silicon tandem cells deliver a champion power conversion efficiency (PCE) of 33.74% (certified 33.37%). Furthermore, the devices exhibit exceptional stability, showing negligible degradation after 4000 h of dark storage and retaining 87.12% of their initial PCE after 1000 h of maximum power point tracking (MPPT) under continuous one‐sun illumination, highlighting the potential of this interfacial strategy for highly stable tandem photovoltaics.

ABSTRACT Anti‐solvent quenching has been widely adopted to fabricate high‐efficiency perovskite solar cells (PSCs). However, this strategy suffers from poor process tolerance and limited scalability, motivating the development of anti‐solvent‐free methods. Here, we report a coordination‐regulated anti‐solvent‐free strategy by introducing sulfolane as an additive into a 2‐methoxyethanol (2ME)‐based perovskite precursor. Owing to the weak coordination capability of 2ME toward Pb 2+ , conventional 2ME processing often leads to uncontrolled intermediate‐phase evolution and needle‐like morphology. However, the interaction between sulfolane and Pb effectively regulates the perovskite precursor environment, stabilizes the iodoplumbate coordination complex, particularly PbI 3 − ‐related species, and thereby modulates perovskite crystallization dynamics. In addition, the residual sulfolane is shown to passivate the defects and traps in the perovskite films. Consequently, the perovskite films exhibit compact and uniform morphology with enhanced grain packing and reduced pinholes. Our resulting champion device with sulfolane additive achieves significantly improved efficiency from 15.03% to 26.02%, with an open‐circuit voltage (V oc ) of 1.18 V. Moreover, the device with sulfolane additive maintains over 87% of its initial efficiency after 2000 h under N 2 atmosphere at 25°C. This work highlights the effectiveness of coordination engineering in enabling scalable and reproducible perovskite fabrication by an anti‐solvent‐free method.

Abstract Curvilinear magnetism offers a powerful route to engineer spin-wave phenomena beyond the limitations of planar architectures. In Curvilinear systems geometry itself acts as an active control parameter. Magnetic nanotubes (MNTs) represent an archetypal three-dimensional platform. In MNTs curvature induces emergent anisotropies, symmetry breaking, and nonreciprocal spin-wave transport without relying on interfacial Dzyaloshinskii–Moriya interactions. In this manuscript, we investigate curvature-engineered spin-wave dynamics in thick-walled Ni 30 Co 70 magnetic nanotubes using broadband, angular-dependent ferromagnetic resonance spectroscopy. We observe pronounced splitting and hybridization of spin-wave modes that are absent in thin shells and planar films. Our measurements revealing the decisive role of finite shell thickness and curvature. The angular evolution of the spectra exhibits a maximum mode splitting near φ H =60 0 . These modes arises from a competition between short-range exchange and curvature-enhanced dipolar interactions. Quantitative analysis using Kittel framework results discrete spin-wave wave vectors in the range ~0.25-0.52 nm -1 . Observed values are in excellent agreement with existing literature based on nanotubes. Our results provide ensemble-level experimental evidence of curvature-induced lifting of mode hybridization, and spectral asymmetry in magnetic nanotubes. By establishing curvature as a robust and scalable design parameter for tailoring magnon spectra. Also, this work advances both the fundamental understanding of spin-wave physics in three-dimensional shells and the realization of reconfigurable, low-loss magnonic circuitry based on curvilinear nanomagnets.