Physics

The performance of all-small-molecule organic solar cells (ASM-OSCs) is often constrained by suboptimal phase separation, resulting from excessive crystallization of the donor and acceptor, which subsequently affects exciton dissociation and charge generation. Here, this study introduces L8-BO-F as a third component into the MPhS-C2:N3 binary system, forming a high-performance ternary system that effectively addresses the aforementioned issue. Upon the introduction of L8-BO-F, the ternary blend film exhibits more ordered molecular stacking, higher crystallinity, increased donor/acceptor interfaces, and finer phase-separated morphology. This optimized microstructure effectively promotes exciton dissociation and charge extraction, reduces the defect density, and suppresses charge recombination. Simultaneously, the elevated charge-transfer state energy contributed by L8-BO-F directly enhances the open-circuit voltage and reduces nonradiative energy loss. Consequently, the MPhS-C2:N3:L8-BO-F ternary device achieves a champion efficiency of 18.16% with simultaneous improvement in short-circuit current density, open-circuit voltage, and fill factor, thereby ranking among the highest-performing ternary ASM-OSCs reported to date. This work presents a ternary strategy that not only refines the active layer morphology but also reduces voltage loss, providing an effective pathway for designing high-performance, low-energy-loss ASM-OSCs.

Chlorine evolution reaction (CER) is a critical electrochemical process in the chlor-alkali industry and water treatment, yet conventional ruthenium (Ru)-based electrodes suffer from severe structural instability under operating conditions. This study proposes an orbital-engineered self-regulating strategy by tailoring the electronic configuration of RuO 2 through tin (Sn) doping. The resulting Sn/RuO 2 nanocatalyst achieves exceptional stability over 800 h at an industrial current density of 1 A cm –2, significantly surpassing RuO 2 catalyst (∼100 h), while maintaining good activity and selectivity (97.9%). Both experimental and theoretical analyses reveal that the orbital hybridization improves p–d coupling between Ru 4d and Sn 5s/5p states by incorporating Sn. This specific orbital interaction triggers a concerted electron density redistribution, which weakens the Ru–O bond by modulating its π* orbital occupancy, lowering the energy barrier for chlorine intermediate adsorption, while simultaneously enhances the antibonding orbital of the Sn–O bond, strengthening its covalent character and effectively anchoring the lattice oxygen against anodic dissolution. The Ru–O–Sn bridge serves as an efficient electron feedback channel that establishes a favorable electronic structure for sustained catalysis, which suppresses Ru overoxidation and maintains stable electronic states throughout prolonged electrolysis. This work establishes an orbital engineering paradigm for designing high-performance nanocatalysts, demonstrating that deliberate modulation of electronic orbitals via strategic doping offers a practical route to simultaneously achieve high activity and exceptional durability under demanding industrial conditions.

The precise control of droplets and bubbles is critical for advancing microfluidics, micro/nano robotics, and lab-on-a-chip technologies, enabling a broad spectrum of applications. However, despite preliminary demonstrations of 3D bubble motion, current strategies are harshly limited by interface dependence. The goal of achieving multidimensional control of bubbles for complex micromanipulation and assembly tasks remains a significant challenge. Here, we propose a novel strategy for 3D micromanipulation by leveraging laser-generated optothermal bubbles within a dimethyl silicone oil medium. Unlike conventional systems where bubble-based microrobots are confined to 2D motion at solid-liquid interfaces, our approach enables complex multidimensional mobility. The optothermal bubble microrobots demonstrated various capabilities, including 2D remote attraction, simultaneous control of multiple bubbles, 3D ascent, and controlled reattachment. We successfully showcase its application in the precise manipulation and assembly of microstructures in 3D space. This 3D bubble microrobot functions as a versatile micromanipulation tool. It may overcome the fundamental limitations of previous bubble-driven systems and opens new avenues for sophisticated microrobotic operations.

Intercalated van der Waals (vdW) magnets have attracted growing interest owing to their rich and highly tunable magnetic properties and their promise for ultracompact spintronic applications. A remarkable example is self-intercalated chromium tellurides (Cr 1+δ Te 2 ), in which spatially ordered chromium atoms occupy the vdW gaps, yielding a variety of known compounds (e.g., Cr 1.25 Te 2, Cr 1.33 Te 2, and Cr 1.5 Te 2 ) that host distinct and intriguing magnetic states. In this work, we uncover the existence of hidden, ordered self-intercalated phases that form spontaneously along with a twisted Cr 1.5 Te 2 phase in chromium telluride nanoflakes grown by chemical vapor deposition. Using wide-field and scanning diamond nitrogen-vacancy center (NV) magnetometry, we unveil intricate magnetic structures in the chromium telluride flakes at the nanoscale and above room temperature. In a small nanoflake, the magnetization prefers an in-plane orientation in its interior with strong anisotropy but is tilted out of plane at the edges. In a large nanoflake, we observe complex magnetic profiles indicating the possible formation of nontrivial localized topological structures. Our work demonstrates the versatility of self-intercalation beyond known phases and the rich magnetic properties in a model vdW magnet, highlighting its great potential for room-temperature spintronic applications.

Two-dimensional WSe 2 has attracted considerable attention owing to its tunable electronic structure and intrinsic catalytic activity. However, the catalytic redox performance of pure WSe 2 remains limited by insufficient charge-transfer efficiency and suboptimal catalytic kinetics in complex oxidative environments. Herein, we constructed a series of ultrasmall WSe 2 clusters via atomic-level regulation. This strategy could modulate their electronic configuration and enhance their catalytic performance. The resulting approximately 2 nm M-WSe 2 (M = Ce, Pt, Fe) clusters exhibited total antioxidant capacity 2.3- to 4.3-fold higher than that of pure WSe 2 . Their multienzyme-like activity was increased by 2.2- to 44-fold, and they exhibited broad-spectrum free radical scavenging ability. These atomic-level modulated clusters effectively protected hepatocytes from oxidative stress damage and inhibited macrophage inflammatory response. In the acetaminophen-induced acute liver injury model, M-WSe 2 significantly alleviated hepatic oxidative damage and restored redox homeostasis, with serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels reduced by approximately 73% and 76%, respectively. Notably, these clusters exhibited favorable biosafety. Through atomic-scale design, this study provided a rational strategy for developing high-performance antioxidant clusters for oxidative stress and inflammation-related liver injury.

Temperature-stimulus-responsive hydrogels with outstanding mechanical and electrical properties have attracted extensive attention in the field of health detection and information encryption due to their unique environmental responsiveness. In this work, a flexible, conductive, tunable thermoresponsive, and antifreezing poly(acrylic acid-acrylamide)/gelatin/lithium chloride (P(AA-AM)/Gelatin/LiCl, PGL) hydrogel was fabricated via a simple one-pot approach. Functional regulator LiCl effectively enhances the mechanical properties of the PGL hydrogel through salting-out effect and phase separation. Also, the transparent-to-opaque transition is reversible and repeatable, and the phase transition temperature can be sensitively adjusted by LiCl mass in the PGL hydrogels. Especially, the PGL 0.8 hydrogel with a strength of 180 kPa, a strain of 620%, and a conductivity of 2.16 S m –1 can serve as the strain sensor (gauge factor of 1.95) and temperature sensor (temperature resistance coefficient of 2.05%/°C at 25–45 °C). Benefiting from its excellent performance, the as-prepared PGL hydrogels can capture real-time electrical signals, including human joint motions, subtle physiological movements, and temperature fluctuations, when utilized as wearable multifunctional sensors. Therefore, the tunable thermoresponsive and antifreezing hydrogel holds promise for human health monitoring and information encryption, meeting theoretical and practical application requirements of flexible wearable sensors.

We report a thermoplastic nanofluidic sensor (exonuclease time-of-flight; X-ToF) fabricated via nanoinjection molding that integrates an immobilized nanoscale enzymatic reactor (INER) directly with a dual in-plane nanopore ToF (DNP-ToF) reader, which not only uses the parameters typically used for resistive pulse sensing (RPS)─normalized event amplitude and time width─but the time taken for a single-molecule to travel between two pores in series. This platform enables the label-free monitoring of complex biological reactions at the single-molecule level. A critical hurdle in integrating such bioenzymatic reactions with RPS is reconciling disparate process step requirements, for example salt effects on an enzymatic reaction and high salt needs for RPS. We addressed this through strategic UV/O 3 surface engineering; an optimized 3.5 min dose created effectively charge-neutral nanopores that maximized capture rates while sustaining a robust ensemble electroosmotic flow (5.33 ± 0.33 × 10 –5 cm 2 V –1 s –1 ) and simultaneously preserving enzyme activity. To demonstrate the sensor’s utility, exoribonuclease 1 (Xrn1) was used as a model. X-ToF successfully deduced the dissociation constant of an input Cas9 RNA to Xrn1 (2.4 ± 0.02 μM –1 ) and monitored in real-time ribonucleotide generation from Cas9 with a cleavage rate of 23 nt/s. Ultimately, this platform serves as a highly versatile tool that can be repurposed for DNA, RNA, or protein sequencing simply by changing the identity of the immobilized enzyme.

High Resolution Image Download MS PowerPoint Slide Integrating self-assembled colloidal nanocrystals with uniform orientation into optoelectronic devices may allow for the significant improvement of charge transport processes. In this work, for this purpose, using the liquid–air interface self-assembly technique and selectively controlling the orientation of CdSe nanoplatelets (NPLs) with short 2-ethylhexane-1-thiol (EHT) ligands in a vertical-configuration photodetector device, we show that the photoconductivity response is substantially improved by the selective arrangement of CdSe NPLs into two distinct assemblies of edge-up (EO) and face-down (FO) orientations compared to the randomly oriented (RO) NPL film deposited by spin-coating. Our devices reveal that EO nanoplatelets significantly enhance response speed, while RO yields higher photocurrent, responsivity and detectivity. The assembled devices, consisting of one-monolayer EO and three-monolayer FO NPL films of comparable vertical film thickness, demonstrate superior photocurrent responses of 8 ms/11.3, 13 ms/4.5, and 15.2 ms for the rise/decay time constants, respectively, compared to 17 ms/18, and 80 ms for the RO for the rise/decay time constants. Despite using only a monolayer of EO NPLs, we achieved a responsivity of 21.04 mAW –1 and a detectivity of 5.77 × 10 10 Jones, compared with the best results from CdSe-based photodetectors reported in the literature. This work provides critical insight for charge transportation management in solution-processed photodetection devices by adjusting the orientation of the two-dimensional quantum structures, paving the way toward fast and atomically thin functional optoelectronic devices. This also demonstrates that facet-specific metal–semiconductor interfaces are another critical factor, in addition to the charge transportation pathway, which can modulate the interfacial electronic structure and recombination dynamics in vertical configuration photodetectors.

Deep ultraviolet (UV) lasers are essential for advanced laser technologies. Currently, only β-BaB 2 O 4 (β-BBO) and CsLiB 6 O 10 (CLBO) are used for nonlinear wavelength conversion in this range, but they face limitations like hygroscopicity and walk-off effects. Thus, alternative materials are needed for efficient frequency conversion. LaBGeO 5 crystals, a promising ferroelectric candidate for UV quasi-phase matching (QPM) devices, have been synthesized with well-developed facets. LBGO showcases remarkable properties: an absorption edge at 195 nm, second-harmonic generation intensity of 1.5 × KDP, and a laser-induced damage threshold of about 2.4 GW/cm 2 (@1064 nm, 10 ns, 10 Hz), with a transmittance of 78% at 266 nm. Its domain-switching ability arises from the distortion of [BO 4 ] tetrahedrons in [GeB 2 O 9 ] rings, marking a significant breakthrough in QPM crystal research and promising advancements in UV laser applications.

High Resolution Image Download MS PowerPoint Slide We report a highly sensitive electric field (E-field) sensor based on a multilayer MoS 2 /multilayer graphene (ML-MoS 2 /MLG) heterostructure with built-in tensile strain. The MLG functions as a bottom source-drain contact, thereby enhancing the charge injection into the ML-MoS 2 channel. The unique device geometry further induces tensile strain in the ML-MoS 2 channel by bending it over the MLG edge, which improves the carrier mobility through reduced electron–phonon scattering. As a result, the ML-MoS 2 /MLG device achieves an average carrier mobility of 75.7 cm 2 V –1 s –1, with values up to ∼108 cm 2 V –1 s –1 at room temperature, significantly exceeding that of conventional metal-contacted MoS 2 devices. Upon exposure to external E-fields, the device exhibits polarity-dependent variations in the drain current arising from field-induced carrier transfer between the ML-MoS 2 channel and trap states at the SiO 2 /channel interface. The E-field sensitivity, defined as the relative change in drain current, increases linearly with the E-field magnitude. Owing to the enhanced charge injection and improved carrier mobility, the ML-MoS 2 /MLG device demonstrates superior E-field sensing performance, achieving a sensitivity around three times that of metal-contacted MoS 2 devices. Notably, the minimum detectable E-field reaches ∼100 V/m, highlighting its potential for atmospheric E-field monitoring toward lightning detection applications.

The application of cosmetic ingredients into hair formulations relies on their extensive characterization and on understanding their mechanisms of action. Specifically, in the case of hair conditioning agents, their efficiency in treating hair must be proved before testing them on real complex formulations. In this work, we investigate the deposition of three cationic polymers onto model surfaces that mimic the negative surface potential of highly damaged hair. Two CHPTAC-cationized lignins (CL0.34 and CL0.61) were evaluated and compared with a commercial polyquaternium (PQ11). The two selected lignin derivatives exhibited different degrees of cationic substitution (DS) and ζ-potential (CL0.34: DS = 0.34 ± 0.01 and ζ-potential = 12.8 ± 0.4 mV; CL0.61: DS = 0.61 ± 0.03 and ζ-potential = 18.8 ± 0.3 mV). Atomic force microscopy (AFM) and quartz crystal microbalance with dissipation monitoring (QCM-D) were used to evaluate the adsorbed layers formed by the polymers and their mechanical properties. Among the tested lignin conditioning agents, CL0.61 exhibited conditioning behavior, forming layers whose properties closely resembled those of the benchmark polymer PQ11. CL0.61 and PQ11 were both efficient at reducing the frizz effect on real bleached hair, effectively overcompensating the hair surface potential, which shifted from negative to positive values, confirming their effective adsorption after conditioning and rinsing. By combining advanced interfacial characterization with structure-property-function relationships, this work provides fundamental insights into polymer adsorption and performance at biointerfaces, supporting the rational design of functional materials and highlighting the potential of cationic lignin derivatives as viable, biobased conditioning agents for future hair-care formulations.

With the rapid expansion of electric mobility and large-scale energy storage systems, the high-value regeneration of graphite anodes from retired lithium-ion batteries has attracted increasing attention. The degradation mechanism of graphite anodes involves multiple factors, including bulk structural damage and interfacial deterioration during cycling. However, state-of-the-art regeneration approaches have been restricted to addressing either structural degradation or interfacial instability in isolation, precluding the attainment of desirable electrochemical performance. To circumvent this fundamental limitation, we propose a phytic acid-assisted regeneration strategy for spent graphite anodes. This approach leverages the abundant intrinsic defects and edge sites present in cycled graphite, which serve as preferential reactive sites for subsequent modification. Upon subsequent facile thermal treatment, phosphorus species are incorporated into the graphite matrix, enabling bulk doping-induced structural reconstruction while simultaneously optimizing the surface chemistry and interfacial properties. Comprehensive characterizations reveal that a fraction of the incorporated phosphorus species diffuses into the bulk lattice and promotes structural restoration. These dopants modulate the local electronic structure and bonding configuration, thereby facilitating lithium-ion adsorption and accelerating diffusion kinetics. Meanwhile, the residual phosphorus species at the surface direct interfacial reactions toward the formation of a robust, inorganic-dominated solid electrolyte interphase (SEI) layer enriched with Li x PO y species, which significantly boosts Coulombic efficiency and long-term cycling stability. As a consequence, the revitalized graphite exhibits excellent electrochemical performance, delivering a specific capacity of 378 mAh g –1 after 500 cycles at a current density of 1 C. Moreover, it exhibits good rate capability, maintaining 330 mAh g –1 at 2.0 C. Further kinetic and interfacial analyses reveal that the improved performance is supported by enhanced charge transfer and ion diffusion, along with a stable and uniform interfacial structure. This work provides a simple and promising route for the high-value utilization of spent graphite and the sustainable design of energy storage materials.

Dopamine (DA) is a key neurotransmitter regulating nervous system function, while epinephrine (EP) is an important hormone reflecting pathological status. The accurate detection of these two molecules is of great clinical significance for the early diagnosis and therapeutic evaluation of related diseases. Metal–organic frameworks (MOFs) exhibit considerable potential in electrochemical sensing; however, pristine MOFs suffer from poor conductivity. In this work, the ligand H 6 L, a derivative of cyclotriveratrylene containing six carboxylic groups, was synthesized. A Co–L MOF was then constructed via a solvothermal method, and its crystal structure was determined and discussed. Then, Co–L was compounded with mesoporous carbon (MC) to give the composites for the modification of an electrode. Benefiting from the MC, the conductivity of the composite was significantly enhanced, and the electrochemical sensors containing the composite for the detection of DA and EP were constructed. Cyclic voltammetry (CV) was used to optimize of testing conditions, and differential pulse voltammetry (DPV) was used to detect the contents of analytes. For the detection of DA, the Co–L@MC(1:2)/GCE ( ES-I ) sensor displayed a linear range of 0.05–35 μM and a detection limit of 1.09 nM (GCE = glassy carbon electrode). For EP, the Co–L@MC(2:1)/GCE ( ES-II ) sensor possessed the linear range of 0.03–75 μM, and the detection limit was 1.55 nM. Meanwhile, both sensors exhibited good selectivity, repeatability, and stability, with all relative standard deviations (RSDs) below 5%.

The catalytic activities of Pt-based nanomaterials strongly depend on their structures, including their compositions, arrangements of surface atoms, and so on. Shape-controlled synthesis has proven to be an efficient route to adjust the surface structure, while alloying has been considered an effective strategy to tune the electronic structure. The former could enhance the catalytic activity by increasing the number of active sites, while the latter could promote intrinsic activity. Previous studies have shown that alloying Pt with Pd can efficiently improve the catalytic activity, while the introduction of Ir can facilitate stability. Therefore, in order to exploit the advantages of both Pd and Ir, we aimed to prepare ternary PtIrPd nanocrystals with a high-index facet structure to further promote the catalytic performance. Herein, we have synthesized PtIrPd trioctahedral (TOH) nanocrystals (NCs) with high-index (441) facets by the electrochemical square wave potential (SWP) method. Hexoctahedral (HOH) NCs with (431) facets were obtained by simply increasing the growth time ( T g ) of the SWP, while tetrahexahedral (THH) NCs enclosed with (210) facets were prepared by raising the upper limit potential ( E U ) of the SWP. The success of the shape-controlled synthesis of these well-defined nanoparticles is mainly due to the periodic adsorption/desorption of oxygen species and crystal growth dynamics. The as-prepared ternary PtIrPd NCs exhibited good catalytic performance for the methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR). Among them, the electrocatalytic activity of PtIrPd THH NCs was 8.6 and 11.0 times greater than that of commercial Pt/C for the MOR and EOR, respectively. Density functional theory (DFT) simulations showed that the introduction of Ir would lead to a downshift of the d -band center and reduce the reaction energy barrier for the conversion of CHOH* to COH*, which made PtIrPd THH NCs exhibit enhanced electrocatalytic activity and stability.

The lunar mare region is rich in basaltic minerals, and in situ resource utilization (ISRU) is a fundamental strategy for sustainable extraterrestrial construction. However, combining electroless plating with basalt fibers for such construction leads to a significant mismatch of coefficient of thermal expansion (CTE) between the fiber substrate and metal coating. Under extreme temperature alternations, this mismatch induces interfacial thermal stress concentration, causing coating peeling and performance failure. To address this issue, this study, using commercial terrestrial basalt fiber as an analogue for lunar basaltic materials, proposes an ISRU-inspired metallized fiber composite suitable for wide-temperature-range applications. By sequential electroless nickel plating and copper electroplating on basalt fibers, a nickel-copper-coated basalt fiber fabric (BF@Ni@Cu) was successfully fabricated, exhibiting high electrical conductivity, excellent electromagnetic interference shielding effectiveness (62.59 dB), and significant joule heating performance. The Ni interlayer forms a CTE gradient transition between the basalt substrate and the outer Cu layer, mitigating interfacial thermal stress. After annealing and PDMS encapsulation, the surface reflection characteristics are effectively regulated. To verify reliability under lunar diurnal temperature variations, cold-thermal shock cycle tests simulating the lunar range (from -196 to 130 °C) are conducted. After 30 cycles, the material maintained structural integrity without cracking or peeling, successfully overcoming interfacial thermal stress concentration. Consequently, the EMI shielding and joule heating performance showed only slight degradation, demonstrating excellent temperature shock resistance. This study not only provides a fiber metallization strategy that retains high performance under extreme temperature alternations but also offers a potential technical pathway inspired by ISRU for multifunctional protection and thermal management materials in future lunar base construction, through the design concept of thermal stress alleviation and failure-mode control via a gradient interlayer.

Facile and quantitative detection of liquid biopsy biomarkers such as microRNAs offers significant potential for precision healthcare; however, conventional biosensing methods rely on enzyme- or label-based workflows that are costly, time-consuming, and labor intensive. Microwave biosensors, particularly split-ring resonators (SRRs), offer an attractive alternative as they enable label-free, noncontact electromagnetic detection through permittivity measurements and are compatible with printed-circuit-board manufacturing. However, the sensitivity of conventional SRR platforms remains insufficient for clinically relevant biomarker detection. Here, we introduce an enzyme-free, label-free microwave biosensing architecture that integrates SRRs with microfluidic channels containing localized bioreceptor-functionalized hydrogel micropillars. Target hybridization within the hydrogel micropillars induces localized changes in complex permittivity, which are transduced into concentration-dependent shifts in the resonant frequency of the SRR capacitive gap. As a proof of concept, the platform is applied to detect the cancer-associated biomarker miR-16-5p using peptide nucleic acid (PNA) probes, which were selected for their neutral backbone, enzymatic stability, and strong hybridization affinity. The hydrogel micropillars act as three-dimensional scaffolds that enhance probe loading and maximize volumetric electromagnetic interaction, representing a departure from conventional planar biointerfaces. Compared with equivalent planar systems, this architecture achieves approximately a 20-fold improvement in detection limit, reaching subnanomolar sensitivity without any amplification or labeling while maintaining single-nucleotide specificity and strong device reproducibility. Beyond being the first demonstration of SRR-based miRNA detection, this work establishes a general strategy for three-dimensional microwave biosensing and positions hydrogel-interfaced resonators as a next-generation platform for sensitive, selective, label-free, and reusable biosensors.

Unipolar barrier architectures enable sensitive detection for computational imaging by blocking majority carriers while allowing efficient minority-carrier transport. However, their performance is often constrained by contact-interface transport limitations that suppress responsivity. Here, we demonstrate an anisotropic unipolar barrier detector based on a BP/MoS 2 /WTe 2 van der Waals heterostructure. By incorporating semimetal WTe 2 as the contact layer with a BP/MoS 2 quasi-unipolar heterostructure, we engineer a robust architecture that synergizes low-resistance carrier extraction with the intrinsic anisotropy of the heterostructure. Crucially, by suppressing the isotropic dark current to prevent signal dilution, this design optimizes the signal-to-noise ratio for polarization-sensitive detection. At zero bias, the detector delivers a responsivity of about 128 mA/W, a specific detectivity of 3.4 × 10 10 cm Hz 1/2 /W, and rise/fall times of 137/170 μs under 638 nm illumination, while achieving a polarization ratio of about 7.8 at 1550 nm. Furthermore, by integrating the device with a digital micromirror device for single-pixel computational imaging, we successfully reconstruct a high-contrast 8 × 8 “H” pattern, outperforming conventional large-area photoresistors. Beyond intensity imaging, the device also enables clear polarization imaging of <0.5 mm. Our findings underscore the significance of semimetal contact engineering in realizing high-sensitivity detection, paving the way for advanced unipolar barrier detectors in computational vision.

Abstract The Overhauser effect (OE) and the Solid effect (SE) are two Dynamic Nuclear Polarization techniques. These two-spin techniques are widely used to create nonequilibrium nuclear spin states having polarization far beyond its equilibrium value. OE is commonly encountered in liquids, and SE is a solid-state technique. Here, we report a single framework based on a recently proposed quantum master equation, to explain both OE and SE. To this end, we use a fluctuation-regularized quantum master equation that predicts dipolar relaxation and driveinduced dissipation, in addition to the standard environmental dissipation channels. Importantly, this unified approach predicts the existence of optimal microwave drive amplitudes that maximize the OE and SE enhancements. We also report optimal enhancement regime for electron-nuclear coupling for maximal enhancement.

Abstract How do populations competing for a common resource convert a spatial advantage into resource monopolization? We introduce a stochastic model for resource competition that decouples the transient discovery phase from monopolization. This agent-based lattice model is inspired by ant foraging that captures competition mediated by attractive and repulsive fields. Initial symmetry breaking is governed by extreme value statistics of first-passage times: a linear spatial disadvantage requires an exponentially larger population to overcome. However, transient superiority cannot stabilize dominance. An interaction bias is necessary to monopolize the resource.

Abstract Toric Code, a cornerstone of the topological order, admits numerous realizations on different planar graphs. We prove that all these realizations share a single, universal entanglement structure in a sense that any Toric Code state can be generated by applying a fixed set of non-local unitaries between identical quasi-one-dimensional quantum ladders. In particular, we consider Toric Code states corresponding to various planar graphs and apply non-local dientanglers to qubits corresponding to non-contractible cycles that satisfy a topological constraint. We demonstrate that, independent of the geometry of the underlying graph, disentanglers convert Toric Code states into a tensor product of Kitaev’s Ladder states. This exact and graph-independent construction reveals that the long-range entanglement characterizing the Toric Code’s topological phase has a precise decomposable structure in a sense that it arises entirely from a specific pattern of entanglement between lower-dimensional subsystems. This structural insight opens new avenues for classification and simulation of topological orders.

Abstract Individual magnetic molecules are promising building blocks for quantum technologies owing to their chemical tunability, nanoscale dimensions and ability to self-assemble into ordered arrays. However, exploiting their properties in quantum information processing requires precise local control of their spin. Here we demonstrate spin–electric coupling for two molecular spin systems—iron phthalocyanine (FePc) and Fe–FePc complexes—adsorbed on a surface. We use electron spin resonance combined with scanning tunnelling microscopy to locally address them and electrically tune them using an applied bias voltage. These measurements reveal a nonlinear voltage dependence of the resonance frequency, linked to the energetic position of the molecular orbitals. We attribute this effect to a transport-mediated exchange field from the magnetic tip, providing a large, highly localized and broadly applicable spin–electric coupling mechanism. Finally, we demonstrate that the spin–electric coupling enables all-electrical coherent spin control. In Rabi oscillation measurements of both single and coupled Fe–FePc complexes, we show that the spin dynamics can be tuned using the exchange field, demonstrating a pathway towards electrically controlled quantum operations.

Orbital order describes a quantum state where occupied orbitals line up in a periodic pattern. Although orbital physics plays a fundamental and universal role in strongly correlated electron systems, the existence and particularly the band-structure fingerprint of orbital order remain a long-standing mystery. Here we report the discovery of rare earth 5d-orbital order developed by the surface states of the intermetallic compound Tb2CoAl4Ge2. Angle-resolved photoemission spectroscopy reveals characteristic nematic features such as Fermi surface deformation and band splitting. These experimental observations can be described by a ferro-orbital order term in the mean-field Hamiltonian. The structural and magnetic origin of such order is excluded by systematic high-resolution neutron powder diffraction and scanning tunnelling microscopy measurements. Our results provide strong evidence for a pure surface orbital order scenario avoiding complications from structural distortion as in colossal magnetoresistance manganites, magnetic order as in iron-based superconductors and charge transfer p-orbital order in cuprates. Whether orbital order can exist with a clear band-structure fingerprint in correlated materials has remained unresolved. Now an orbital order from rare earth 5d electrons without structural or magnetic order is seen in an intermetallic compound.