PDF Summaries - vdW materials

Nature, Published online: 15 July 2026; doi:10.1038/s41586-026-10762-7

A rich variety of both integer and fractional high-Chern insulators are observed in a moiré system composed of Bernal bilayer graphene and rhombohedral tetralayer graphene.

Nature, Published online: 15 July 2026; doi:10.1038/s41586-026-10765-4

Polydopamine-pillared composite graphene oxide membranes with tunable and stable interlayer spacing, featuring controllable interlayer spacing, are capable of sieving hydrated rubidium and potassium ions and delivering continuous freshwater production at high levels.

We introduce graphene nanohelicoids, geometric analogues of graphene nanoribbons, in which the honeycomb lattice is embedded on a helicoidal surface. Starting from the three-dimensional helical structure, we construct effective one-dimensional lattice models with band structures characterized by a momentum-shifted particle-hole relation $E_v(k)=-E_c(k+\pi)$ that reflects an anti-chiral symmetry arising from the nonsymmorphic symmetry. A systematic investigation of graphene nanohelicoids using the tight-binding approximation reveals a number of trends upon varying width and edge orientation, for instance, alternating transitions between semiconducting and metallic regimes. As the structure width varies, the band gap periodically closes and reopens, accompanied by an alternating Zak phase that switches between trivial and nontrivial. We derive an analytic tight-binding model and introduce a continuous deformation of the graphene nanohelicoids that explains the origin of width-dependent band inversion and alternating Zak phase.

As a promising member of the graphene‐skinned Cu powder family, this material integrates the properties of graphene with the inherent advantages of Cu. However, controlled growth on curved surfaces remains challenging due to curvature‐induced stress, catalytic heterogeneity of molten Cu, and limited carbon migration. Using DFT, AIMD, LS‐DYNA, and experimental verification, we show that curvature introduces a size‐dependent energy barrier (181.87 eV for 10 nm vs. 21.40 eV for 10 µm) and elastic instability, triggering six‐branched domains when the branch length exceeds a critical value l c = 0.0092 R (where R is the powder radius). Surface premelting lowers the CH 4 decomposition barrier to 1.10 eV, boosting carbon supply by 10 3 ‐fold, yet simultaneously suppresses carbon surface diffusion by 10 4 times. Consequently, powders ≤10 µm exhibit ultrahigh nucleation density (up to 7.27 × 10 5 N/mm 2 ) and low growth rates (0.92–3.64 µm/min). These effects intensify with decreasing particle size, whereas powders ≥50 µm behave similarly to flat foils. This work clarifies the synergy between curvature‐induced elastic instability and premelting‐mediated kinetics, identifies suitable Cu powder sizes for CVD graphene growth, and provides a theoretical foundation for optimizing CVD parameters (e.g., temperature and carbon flux) to obtain high‐quality graphene coatings for high‐performance composites.

In this work, the effect of partial substitution of Mn by Ni on the structural and electronic properties of kesterite systems Cu2NiXY4 (X = Sn, Ge, Si; Y = S, Se) was studied using density functional theory (DFT). The mBJ+U method was used to characterize the bandgap more accurately. To the best of our knowledge, a systematic comparative study of Mn substitution in the entire Cu2NiXY4 (X = Sn, Ge, Si; Y = S, Se) family has not been previously performed. Due to crystallographic constraints of the kesterite unit cell, the substitution of a single Ni atom with Mn corresponds to 50%. This configuration was chosen to study the effect of Mn substitution on the structural and electronic properties of Cu2NiXY4 (X = Sn, Ge, Si; Y = S, Se) compounds, whereas the study of lower concentrations requires the use of a supercell and is the subject of further research. The calculation results show that the partial substitution of Ni with Mn preserves the tetragonal structure of kesterite and significantly alters the electronic structure. In all the compounds studied, the bandgap decreases from 1.028-3.397 to 1.007-3.333 eV. For example, in the Cu2NiSnS4 system, the bandgap width decreases from 1.59 eV to 1.49 eV. The narrowing of the bandgap results from hybridization between the Mn-3d, Cu-3d, and S/Se-p orbitals near the band edges, leading to a redistribution of electronic states around the Fermi level. The results demonstrate that Mn substitution is an effective strategy for controlling the electronic properties of Cu2NiXY4 kesterites, offering great promise for use in optoelectronic devices where adjustable bandgaps are required.

Nature Reviews Physics, Published online: 15 July 2026; doi:10.1038/s42254-026-00973-2

Roanne Aves describes a platform to integrate graphene-FET based microfluidic modules into one experimental workflow.

Harnessing Rashba spin-orbit interaction and related spintronic functionalities has traditionally relied on metallic surfaces or interfaces containing elemental heavy metals. Here, using first-principles calculations and Cu(001)/WO$_3$(001) as a model heterostructure, we show that interfacing a light metal, Cu, with a band insulator, WO$_3$, yields an interface state that exhibits a robust Rashba spin splitting arising from the interplay between linear and cubic Rashba effects. The spin splitting is driven by the strong spin-orbit coupling of W atoms and enabled by W-Cu orbital hybridization at the interface. The cubic Rashba contribution asymptotically grows with Cu thickness and can be explained in terms of cross-coupling between the vacuum/Cu and Cu/WO$_3$ interfaces. This interfacial cross-coupling, however, diminishes at larger Cu thicknesses, allowing us to extract the intrinsic cubic Rashba parameter, which has a giant value of approximately -1.93 eV $\r{A}^3$. In contrast, the linear Rashba parameter is only weakly affected by this cross-coupling and varies from approximately 0.30 to 0.49 eV \r{A}. We further show that sizable linear and cubic Rashba effects persist across several interface geometries and Cu surface orientations, including (110) and (111). Our work identifies the Cu/WO$_3$ interface as a novel light-metal/heavy-element-based oxide platform for exploring the rich spectrum of Rashba physics, including linear and nonlinear spin-orbit phenomena.

Twisting a van der Waals bilayer changes not only the moir\'e periodicity but also the local stacking and interlayer hybridization. Here, we show, using fully relaxed first-principles calculations including spin--orbit coupling, band unfolding, and Brillouin-zone-integrated densities of states, that bilayer PtTe$_2$ exhibits a non-monotonic evolution between gapless and gapped electronic regimes. The $7.34^\circ$ structure remains gapless, whereas finite direct gaps appear at the sampled intermediate angles. The gap closes at the sampled $60^\circ$ configuration and reopens at higher angles. The direct gap shows an overall increase with the minimum local interlayer Pt--Pt separation, although the complete distribution of local stacking environments is required to account for deviations from this trend. At $7.34^\circ$, the low-energy states are concentrated predominantly in the AA-like regions of the otherwise gapless moir\'e cell. Controlled interlayer-separation scans show that increasing the layer spacing removes the near-$E_F$ crossings and opens a gap, consistent with weakened interlayer Te-$p_z$ hybridization. These results identify the redistribution of interlayer hybridization as the microscopic origin of the re-entrant gap evolution in twisted bilayer PtTe$_2$.

We study strongly correlated many-body states in alternating twisted trilayer and tetralayer MoTe$_{2}$. By sliding the top layer with respect to others and applying a perpendicular electric field, a variety of band structures can be realized. In many cases, the topmost hole band has unity Chern number and its quantum geometric properties can be tuned to some extent. Exact diagonalizations suggest that fractional Chern insulators are stabilized in certain parameter regimes but not in some regimes even when the band is topological. This contrast is attributed primarily to different quantum geometries as quantified by the trace condition. Our results demonstrate that sliding can serve as a useful knob for probing many-body states in moir\'e systems.

This work reports a printable, ultrasoft, highly stretchable, adhesive, breathable hydrogel engineered that is radically tuned by controlling the precursor pH level for simultaneous biosignal monitoring. The hydrogel based on porous laser-induced graphene composites synthesized using in situ laser reduction with polydopamine and tannic acid exhibits ultrasmall Young’s modulus of 1.08 kilopascal, super high stretchability of ~8000%, and desirable conductivity and adhesive strength for through-hair signal monitoring even in the presence of sweat. The excellent skin conformability of the hydrogel provides the resulting electrodes with low skin contact impedance at both wet and dry conditions, a high signal-to-noise ratio, and motion artifact–free monitoring of electrophysiological signals. Combined with electrodermal activity and strain sensing from the facile patterning/printing of the reusable and storable gel, the proof-of-concept demonstration of the device platform is showcased for anxiety monitoring and nerve rehabilitation studies.

Interlayer excitons in transition‐metal dichalcogenide (TMD) van der Waals heterostructures offer long lifetimes, out‐of‐plane dipoles, and valley‐selective optical selection rules. However, active and energy‐efficient control of their formation and recombination remains elusive. Here we demonstrate an interface‐engineering strategy that enables magnetic control of interlayer excitons by inserting a monolayer ferromagnet, CrSe 2 , as an atomic‐scale spin‐valve spacer within a twisted WSe 2 homobilayer. At low temperature, the twisted WSe 2 bilayer supports highly efficient conversion from intralayer to interlayer excitons, providing a sensitive platform to probe interlayer charge transfer. Introducing CrSe 2 suppresses interlayer coupling and produces pronounced thermomagnetic signatures near the Curie temperature (∼65 K), evidencing strong coupling between magnetic fluctuations and exciton dynamics. Under external magnetic fields up to 9 T, the interlayer‐exciton emission is reversibly modulated while intralayer emission is enhanced, consistent with spin‐selective tunnelling that regulates interlayer charge transfer. First‐principles calculations support CrSe 2 ‐mediated spin filtering and reveal stacking‐angle‐dependent charge transfer. These findings establish magnetic spin filtering as an effective strategy for manipulating excitonic states, opening pathways toward spin–exciton hybrid architectures and quantum optoelectronic devices at the atomic scale.

Three-dimensional fractional quantum Hall phases offer a route to intrinsically higher-dimensional topological order beyond simple stacks of two-dimensional quantum Hall liquids. Such phases can exhibit non-foliated, intrinsically three-dimensional entanglement structures, exponentially large topological degeneracies and quasiparticles with irrational braiding statistics. Their microscopic realization has remained elusive because Landau quantization in three dimensions generally leaves dispersive one-dimensional bands, favoring metallic and density-wave states over incompressible fractional liquids. Here we show that large-angle twisted van der Waals multilayers provide a practical route around this obstruction. Large twist angles suppress coherent interlayer tunneling through momentum mismatch, while the atomic-scale layer separation preserves strong interlayer Coulomb interactions. Using Monte Carlo calculations to compare the energies of an extensive set of 862 competing trial wavefunctions, we find that generalized Halperin states with quantum coherence extending across multiple consecutive layers are stabilized. In experimentally accessible magnetic-field regimes, these states replace the metallic spontaneous-interlayer-coherent phases that dominate conventional untwisted graphite-like multilayers. The resulting liquids realize non-foliated fractional quantum Hall order closely related to fractonic topological order, hosting quasiparticles with rational electric charges but irrational braiding statistics. Their large topological degeneracy and non-rational statistical phases may offer unconventional resources for quantum information storage and processing. Our results establish twisted van der Waals multilayers as a realistic materials platform for three-dimensional fractional Hall matter beyond conventional two-dimensional quantum Hall systems.

Nature, Published online: 15 July 2026; doi:10.1038/s41586-026-10709-y

A 54-qubit realization of non-Abelian S3 topological order demonstrates that combining anyon braiding with fusion enables universal topological quantum computation.

Rhenium disulfide (ReS2) is a low-symmetry transition metal dichalcogenide (TMDC) exhibiting strong in-plane anisotropy, weak interlayer coupling, and stacking-dependent physical properties. While anisotropic thermal conductivity has been reported in bulk ReS2, experimental studies on stackingdependent thermal conductivity and its thickness evolution in the few-layer regime remain largely unexplored. Here, we have extracted the thermal conductivity of freestanding, few-layer ReS2 samples (thickness 10 nm) using polarization-resolved optothermal Raman thermometry after correcting for polarization dependent absorbance. All measured ReS2 samples show pronounced in-plane anisotropic thermal conductivity. Notably, the ~3.5 nm AA-stacked flake shows higher thermal conductivity than the AB-stacked flake of the same thickness, highlighting the influence of stacking order on phonon transport. The in-plane thermal conductivity displays a non-monotonic dependence on thickness over the 2.5 to 8 nm range which is supported by density functional theory (DFT) calculations. These findings provide key insight into anisotropic phonon transport in low-symmetry 2D materials and highlight the potential of few-layer ReS2 for nanoscale thermal management and thermoelectric applications.

We combine first-principles density-functional theory, Berry-curvature analysis, semiclassical Boltzmann transport, and atomistic spin dynamics to establish hexagonal NiS as a compensated 3d altermagnetic semimetal in which topology, magnetism, and lattice dynamics are intrinsically intertwined. The rotational coset symmetry of the NiAs lattice produces momentum-dependent spin splitting characteristic of altermagnetism. With spin-orbit coupling, gapped Dirac-like crossings generate intense Berry-curvature hot spots and nearly compensated electron-hole pockets. This leads to a large and anisotropic intrinsic spin Hall conductivity comparable to that of several 4d, 5d metals, a symmetry-allowed anomalous Hall response despite zero net magnetization, and nonsaturating magnetoresistance exceeding 10000 percent. On the magnetic side, first-principles determination of the exchange tensor reveals dominant long-range superexchange and sizable anisotropic interactions, quantitatively reproducing the experimental Neel temperature. Our results identify NiS as a model 3d platform in which carrier compensation, altermagnetic symmetry, Berry-curvature driven transport, and lattice-sensitive magnetism coexist within a single symmetry framework, offering a design principle for multi-functional quantum responses in correlated transition-metal compounds.

Magnetic order in materials combining localized rare-earth moments with itinerant transition-metal sublattices generates internal fields whose lattice imprint is rarely accessed directly. In Gd pyrochlore ruthenate, we find that a single terahertz spectrum resolves an exchange-split Gd$^{3+}$ mode and an optical phonon. Their coupled evolution quantifies the internal field, oriented as predicted for cluster-multipolar order, and reveals a Gd-ordering transition elusive to bulk thermodynamic probes, establishing a unified framework for accessing magnetic and lattice responses in correlated quantum materials.

Science Advances, Volume 12, Issue 29, July 2026.

Heavy-fermion superconductors are mostly associated with f-electron materials with Kondo lattices, while known d-electron heavy-fermion-like systems are often linked to orbital-selective local moments, Hund-metal physics, or a charge-density-wave mechanism. Here we report Mo4PtGa17, a noncentrosymmetric itinerant d-electron superconductor with a geometrically frustrated breathing-pyrochlore Mo lattice. Thermodynamic, transport and NMR measurements reveal heavy-fermion-like behavior superconductivity and dominant ferromagnetic spin fluctuations near a ferromagnetic instability. Theoretical calculations identify nearly flat bands, van Hove singularities and Kramers nodal lines near the Fermi energy, derived intrinsically from Mo-4d states and are robust against on-site electronic correlations. These results suggest that the geometrically frustrated lattice in Mo4PtGa17 generates an intriguing electronic structure that enhances the density of states, spin susceptibility and quasiparticle mass. Mo4PtGa17 therefore identifies a unique route to heavy-fermion-like superconductivity in d-electron materials through geometrical frustration, different from the previously reported systems.

Three-dimensional (3D) iodide double-perovskite (elpasolite) semiconductors have attracted interest as potential lead-free metal-halide absorber layers for solar applications. Although studied extensively by computational methods, they have remained largely inaccessible synthetically, consistent with their predicted thermodynamic instability. Here, we report the first synthesis of bulk Cs2AgBiI6, demonstrating both microcrystalline and thin-film forms. Microcrystalline powders of Cs2AgBiI6 were prepared via anion exchange from phase-pure Cs2AgBiBr6 microcrystals. The resulting iodide elpasolite shows broad absorption throughout the visible with a 1.70 +/- 0.05 eV optical bandgap and near-infrared photoluminescence centered at 1.03 eV. We identify the elimination of trace moisture in bulk Cs2AgBiBr6 as the critical factor enabling complete halide exchange and isolation of bulk Cs2AgBiI6 with phase purity. In inert atmosphere, microcrystalline Cs2AgBiI6 shows no decomposition when stored for months at room temperature or heated to ~70 {\deg}C, and it appears equally stable in dry air. Building upon these insights, we then demonstrate the preparation of phase-pure Cs2AgBiI6 films by flash thermal evaporation of Cs2AgBiBr6 followed by anion exchange. Photoconductivity measurements on such Cs2AgBiI6 films demonstrate photocarrier generation and transport, marking the first optoelectronic measurement on this elusive 3D iodide double perovskite.

We employ polarization-resolved Raman spectroscopy combined with first-principles calculations to study the sodium-ion lattice dynamics in a sodium zig-zag ordered cobaltate compound Na$_{0.5}$CoO$_2$. We detect two sodium phonon modes for the first time, and their mode frequencies are consistent with first-principles phonon calculations based on an orthorhombic unit cell. We find that they appear below around $T^*\sim300\pm50$K with large linewidth broadening, much lower than the sodium zig-zag ordering temperature $T_\text{S}\sim460$K, and then narrow at lower temperatures. We interpret the sodium-phonon anomalies occurring at $T^*$ as a dynamical-to-static crossover involving mainly the motion of sodium ions. Our results suggest that the gradual freezing of the sodium ions and the well-defined static sodium-zigzag order below $T^*$ set the stage for the emergent electronic and magnetic orders in the CoO$_2$ layer of Na$_{0.5}$CoO$_2$.

Extended domain-wall networks that emerge in moir\'e materials provide a distinct platform for quasi-one-dimensional electronic states. However, the interaction-driven orders in confined networks remain largely unexplored. Here, we discuss superconducting (SC) correlations in interacting helical domain-wall-ring networks in the closed topological domains formed within the moir\'e patterns of an underlying twisted bilayer honeycomb lattice. We first analyze the system within the framework of an infinite-size theory and show that inter-ring SC-pair tunneling is renormalization-group relevant and thus enhances SC correlations through inter-ring phase locking. To address finite-size effects resulting from the ring-network geometry, we present a self-consistent variational approach. Our analysis shows that even in the regime where the infinite-size theory predicts strongly coupled pair tunneling, the induced phase-locking scale remains strongly suppressed. In contrast, the SC scaling dimension continues to decrease with stronger inter-ring density-density interaction and a decreasing twist angle, while remaining insensitive to the pair-tunneling strength. This discrepancy demonstrates that ring networks do not simply approach their infinite-size counterparts but can exhibit qualitatively distinct collective behavior. Our study highlights how the interplay of confinement effects and ring-network geometry can reshape SC correlations.

Advanced Functional Materials, EarlyView.

The conventional characterization of topological materials relies on topological invariants calculated from the entire set of occupied bands. However, when a system possesses rotational symmetry, the occupied Hilbert space can be decomposed into multiple subspaces labeled by distinct rotation eigenvalues. We show that this decomposition reveals hidden topological states characterized by a novel $\mathbb{Z}_2^n$ topological invariant, where $n$ is the number of subspaces, while the conventional $\mathbb{Z}_2$ invariant may fail to detect the topology hidden in the rotation subspaces. Remarkably, time-reversal symmetry pairs conjugate rotation eigenvalues and guarantees that the two subspaces have the same $\mathbb{Z}_2$ invariants, making the topology always hidden from the conventional global invariant. We formulate the theory of rotation-subspace topology and demonstrate its material realization in bulk CsCl. Using first-principles calculations and symmetry analysis, we show that bulk CsCl, which is diagnosed as topologically trivial by the conventional approach, features a nontrivial $\mathbb{Z}_2^3$ invariant along the $\Gamma$-R path and a nontrivial $\mathbb{Z}_2^4$ invariant along the $\Gamma$-Z and M-R paths, leading to double Weyl points on the (111) and (001) surfaces, respectively. The subspace $\mathbb{Z}_2^n$ invariant proposed here serves as a necessary refinement for symmetry-protected topological phases and will facilitate the identification of a large class of topological states overlooked by existing diagnostics.

Author(s): Meijun Wang, Ying Liu, Yefeng Li, Yong-An Zhong, Lei Jin, Xuefang Dai, Guodong Liu, and Xiaoming Zhang

Two-dimensional altermagnets (AMs) with tunable electronic and topological properties offer promising opportunities for next-generation spintronic and optoelectronic applications. Here, we predict that monolayer VO (ML-VO) is a two-dimensional AM semiconductor with collinear magnetic ordering and $d…

[Phys. Rev. B 114, 014417] Published Tue Jul 14, 2026

Structural, thermodynamic and electrical transport properties of TbAuPb were investigated on single crystals. The compound was found to crystallize with the cubic MgAgAs-type structure characteristic of half-Heusler materials. It orders antiferromagnetically at TN = 5 K and undergoes a transition into a different antiferromagnetic phase emerging in high magnetic fields. Electrical transport in TbAuPb exhibits a multiband character, with a predominance of hole-like carriers. Angular magnetoresistance evolves systematically with applied magnetic field and changes its symmetry near the spin-reorientation transition, highlighting strong coupling between the charge transport and the magnetic order. The results of first-principles calculations indicate that TbAuPb is a band inverted semimetal in the non-magnetic state, which becomes topologically trivial in the field-induced ferromagnetic state.

Author(s): JunYing Hu, GuangYang Dai, Liang Ma, JingKai Bi, JianYong Chen, and ZhiWei Men

Topological insulators (TIs) constitute a unique class of quantum materials owing to their topology-protected electron states. While pressure is an effective way to induce superconductivity in TIs, superconductivity often appears after phase transition or structural disorder. Therefore, identifying …

[Phys. Rev. B 114, 024103] Published Tue Jul 14, 2026

Molybdenum disulfide (MoS$_2$) is a semiconductor whose vibrational and excitonic properties are highly sensitive to layer number and structural disorder. We demonstrate the growth of MoS$_2$ monolayers on inert, electronics-compatible SiO$_2$ substrates using room-temperature pulsed laser deposition (PLD). Control of the process parameters enables tuning from monolayer to multilayer films, which we investigate by multiwavelength Raman spectroscopy. The evolution of the Raman-shift difference between the $E_{2g}^{1}$ and $A_{1g}$ modes, combined with an assessment of defect density, tracks film growth as a function of the number of deposition laser pulses. Although excitonic effects strongly influence the optical response of two-dimensional transition-metal dichalcogenides, experimental reports of symmetry-selective exciton-phonon coupling remain limited. We provide experimental evidence of symmetry-dependent exciton-phonon coupling in PLD-grown monolayer MoS$_2$. Specifically, we observe modulation of the resonant behaviour of the out-of-plane $A_{1g}$ and in-plane $E_{2g}^{1}$ modes, related to their different coupling to A excitons, predominantly derived from Mo $d_{z^2}$ orbitals, and C excitons, characterized by mixed orbital contributions from Mo $d_{z^2}$ and S $p_x$ and $p_y$ states. Comparison with mechanically exfoliated monolayers reveals the role of growth-induced defects in modulating these interactions. These findings establish room-temperature PLD as a viable approach for growing two-dimensional MoS$_2$ on inert, electronics-compatible substrates and provide insight into the interplay between excitonic resonances and growth-induced disorder in two-dimensional MoS$_2$.

We theoretically study emergent electromagnetic responses in Weyl semimetals. Focusing on magnetic Weyl semimetals, we develop a general theory of emergent induction driven by magnetic dynamics. We show that magnetoelectric (ME) responses in Weyl semimetals give rise to emergent induction mediated by magnetization dynamics. Using effective two-band models for magnetic Weyl semimetals, we derive a formula for the ME response that includes both intraband and interband contributions. The resulting formula shows that the intraband contribution is proportional to the relaxation time $\tau$, whereas the interband contribution is associated with the separation of the Weyl nodes. Applying the general formula to a model of polar Weyl ferromagnets, we demonstrate that the dynamics of the toroidal moment is closely related to the emergent inductive response in polar Weyl ferromagnets, as recently discovered by Suzuki et al. [Y. Suzuki et al. arXiv:2607.12322]. The chemical-potential dependence of the inductance indicates that the emergent electromagnetic response is enhanced in the energy range of the Weyl dispersion, reflecting the topological nature of Weyl semimetals.

The realization of large-scale silicon quantum processors requires spin qubits compatible with advanced semiconductor manufacturing technologies, demanding lithographic processes that combine nanometer-scale precision with exceptional uniformity. Although the highest-performing silicon spin qubits demonstrated to date have relied on electron-beam (e-beam) lithography, its serial exposure process limits reproducibility studies and wafer-scale fabrication. Here, we demonstrate high-performance silicon metal-oxide-semiconductor (SiMOS) spin qubits fabricated using extreme-ultraviolet (EUV) lithography in a 300 mm semiconductor pilot line. We report wafer-scale quantum-dot uniformity metrics, including 100 % room-temperature gate-to-gate leakage yield and sub-nanometer control of critical gate dimensions. We characterize four double-dot systems realized in two triple-quantum-dot devices. Gate set tomography (GST) reveals consistently high fidelities across all four systems, with values up to 99.8 % for SPAM, 99.9 % for single-qubit gates, and 99.1 % for two-qubit gates. The devices exhibit highly reproducible exchange turn-on characteristics of 10-13 dec/V, indicating high fabrication uniformity enabled by EUV patterning. These results establish EUV lithography as a viable manufacturing technology for quantum processors based on high-fidelity SiMOS spin qubits.

Author(s): Pietro Maria Forcella, Cesare Tresca, Antonio Sanna, and Gianni Profeta

Mercury chalcogenides are a class of materials that exhibit many structural phases under pressure, hosting exotic physical properties, including topological phases and chiral phonons. In particular, recent experimental results [Zhang et al., Phys. Rev. B 110, L060502 (2024)] on HgS report a new sup…

[Phys. Rev. B 114, 034506] Published Tue Jul 14, 2026

Author(s): Daisuke S. Shimamoto, Keiko Shimamoto, Sonia Mahmoudi, and Samuel Poincloux

The ability of a fabric to be knitted into a textile can be determined on the basis of the topology of its pattern.

[Phys. Rev. X 16, 031006] Published Tue Jul 14, 2026

Topological insulators have been explored extensively for spin-charge interconversion via magnetic interfaces, yet the true response of their spin-charge conversion, particularly in the absence of an external magnetic field, remains to be studied. Here, we report electric-field control of spin-charge conversion in the topological insulator Bi$_2$Te$_3$ with the antiferromagnetic multiferroic BiFeO$_3$, employing a nonlocal spin transport device. A systematic thickness dependence of the spin transport across the interface between Bi$_2$Te$_3$ and BiFeO$_3$ reveals a signature of topological surface-state-dominated spin transport in the bilayer system. The spin-charge conversion remains robust for thicknesses above 10 nm but falls rapidly with reducing thickness and vanishes at 5 nm. This is consistent with the hybridization-induced emergence of a trivial insulating phase, which is supported by the coherency factor estimated from the magnetoconductance of Bi$_2$Te$_3$. These results establish that spin-momentum-locked surface states dominate interfacial spin transport in the decoupled regime. Beyond presenting efficient spin-charge interconversion at an entirely insulating magnetic interface, this work also highlights sputter-deposited Bi$_2$Te$_3$ as a high-quality and scalable platform for integrating quantum materials into devices. The nonlocal spin transport approach presented here provides a simple and direct evidence of spin-charge conversion and opens an efficient and practical pathway toward designing energy-efficient spin-based devices.

Small, EarlyView.

Recrystallization in disordered solids proceeds through a sequence of local structural rearrangements that are difficult to resolve using conventional diffraction analysis. In amorphous and partially ordered materials, subtle variations in diffuse scattering, short-range order, and defect-mediated symmetry emergence encode the pathways through which ordering initiates and propagates. Here, we introduce a latent space framework for mapping these pathways directly from \textit{in situ} 4D-STEM diffraction data. A convolutional autoencoder provides a compact representation of structural motifs, and unsupervised clustering identifies recurring microstructural states, including amorphous, paracrystalline, crystalline, twinned, and hybrid intermediates. By tracking these states across temperature, we construct phase trajectory models that reveal the topology of the recrystallization landscape, including metastable basins, branching pathways, hybrid states, and temperature-dependent reorganizations of accessible states. Applied to ion irradiated GaAs, this approach uncovers two distinct recrystallization regimes separated by a transition near 250\textdegree{}C. At low temperature, recrystallization is growth-dominated and dominated by the persistence of amorphous and crystalline states. At high temperature, the transformation landscape reorganizes: hybrid and faulted states become metastable precursors to twinning, polycrystalline regions stabilize, and twinned structures emerge as dominant end states. The latent space representation also identifies amorphous patterns with weak symmetry signatures that precede recrystallization. This reveals structural precursors to ordering that are not captured by conventional descriptors give new insights into how recrystallization is initiated.

We identify a three-dimensional system that exhibits long-range entanglement at sufficiently small but nonzero temperature--it therefore constitutes a quantum topological order at finite temperature. The model of interest is known as the fermionic toric code, a variant of the usual 3D toric code, which admits emergent fermionic point-like excitations. The fermionic toric code, importantly, possesses an anomalous 2-form symmetry, associated with the space-like Wilson loops of the fermionic excitations. We argue that it is this symmetry that imbues low-temperature thermal states with a novel topological order and long-range entanglement. Based on the current classification of three-dimensional topological orders, we expect that the low-temperature thermal states of the fermionic toric code belong to an equilibrium phase of matter that only exists at nonzero temperatures. We conjecture that further examples of topological orders at nonzero temperatures are given by discrete gauge theories with anomalous 2-form symmetries. Our work therefore opens the door to studying quantum topological order at nonzero temperature in physically realistic dimensions.

Author(s): Jing-Min Fan, Fan-Di Sun, Ai-Lei He, Wei-Wei Luo, and Yi-Fei Wang

This work develops a method for constructing nearly flat bands with arbitrary Chern number $C$ in momentum space and further reconstructing their corresponding real-space models. In the two-band case, starting from a known topological flat band with $C=1$, we systematically generate nearly flat band…

[Phys. Rev. B 114, 055116] Published Tue Jul 14, 2026

Chemical Vapor Deposition (CVD) is a promising method for scalable synthesis of two-dimensional transitional metal dichalcogenides (TMDs) such as MoS2, but challenges in reproducibility and controllability persist due to an incomplete understanding of their dynamic growth mechanisms. While in-situ characterization methods could provide valuable insights, it remains challenging to track a large ensemble of crystals to enable quantitative, statistical analysis. Here, we address this gap by developing and applying a semi-automated image processing pipeline to analyze in-situ optical microscopy footage of MoS2 growth. This framework enables the high-throughput reconstruction of complete growth trajectories for over 400 individual crystals from a single experiment. Our statistical analysis demonstrates that MoS2 crystallization is governed by an edge-attachment-limited mechanism rather than by precursor diffusion. Furthermore, MoS2 crystals exhibit non-competitive growth, indicating that precursor supply does not limit the growth of neighboring flakes until physical impingement occurs. These findings provide direct, quantitative evidence that advances the fundamental understanding of TMD growth, establishing a powerful methodology for rational optimization of the CVD growth of two-dimensional materials.

Topological structuring of light inevitably leverages on optical coherence to ensure that the imparted spatial phases are preserved, requiring highly coherent sources or coherence engineering embedded in the design. Now we show that thermal light can be spatially engineered to carry optical topologies in the form of Skyrmions. Such topologies are immune to time averaged decoherence, a fact we leverage on in reverse to create metasurface mediated incoherent topologies from a thermal source. The pristine nature of our measured Skyrmions validates the approach, while simulations reveal how coherence management in the metasurface design would further enhance the functionality. Remarkably, the generation stage inherits robustness from the topology, remaining immune to material and fabrication defects. Our work reports the first topologies from purely thermal light, opening a path to exploiting topology in ubiquitous everyday light sources.

Accurate constitutive modeling of hot deformation behavior is essential for designing thermomechanical processes in advanced structural alloys. Conventional Arrhenius-type and empirical models do not adequately capture the combined effects of strain hardening, dynamic recovery (DRV), and dynamic recrystallization (DRX) across broad processing conditions. In this study, two Stacked Residual Physics-Informed Neural Networks (STAR-PINNs) were developed to simulate the hot deformation response of a Mo-rich $\alpha+\beta$ titanium alloy (Ti-6Al-4Mo-1V-0.1Si). The Enhanced STAR-PINN incorporated thermomechanical constitutive constraints, while the DRX-Aware STAR-PINN employed a dual-output architecture to account for recrystallization kinetics. Both models used a shared residual encoder trained on experimental flow stress data collected at temperatures from 800 to 1050 degrees C and strain rates between 0.01 and 10 per second. Physics-informed constraints, including thermal softening, strain-rate sensitivity, strain hardening, and post-peak softening, were enforced through automatic differentiation. The DRX-Aware model further integrated JMAK-Avrami regularization, DRX saturation constraints, and Arrhenius-based consistency with tunable parameters, directly linking the predicted DRX fraction to stress output via latent-feature fusion. The DRX-Aware STAR-PINN achieved RMSE = 11.69 MPa, MAE = 4.83 MPa, R^2 = 0.9850, and a cross-validated RMSE of 12.47 +/- 0.26 MPa. This model accurately reproduced temperature-dependent flow curves, DRX kinetics, and Zener-Hollomon relationships, while maintaining physically consistent constitutive behavior. These results demonstrate that physics-informed deep learning provides a robust and interpretable framework for constitutive modeling, offering a practical approach for advanced process modeling of titanium alloys.

Proximity-induced superconductivity in strongly correlated insulators provides a versatile route for engineering quantum states of matter and artificial systems with tailored functionalities. However, microscopic interplay between superconductivity and correlated insulating states remains poorly understood. Here we use ultralow-temperature scanning tunnelling microscopy (STM) to systemically investigate superconducting proximity effects in a charge-transfer insulator. Via STM tip manipulation, atomically sharp lateral junctions composed of superconducting monolayer H-NbSe2 and charge-transfer insulating monolayer T-NbSe2 are constructed, enabling direct access to tunable coupling regimes. In the weak-coupling regime, there is a robust proximity-induced superconducting gap in T-NbSe2, with a reduced gap value relative to that of H-NbSe2. Upon entering the strong-coupling regime, T-NbSe2 exhibits a superconducting gap comparable to that of H-NbSe2, accompanied by pronounced particle-hole-symmetric in-gap bound states, consistent with Yu-Shiba-Rusinov-like excitations. These findings establish monolayer H/T-NbSe2 lateral junctions as a model platform for elucidating superconducting proximity effects in strongly correlated charge-transfer insulators.

Author(s): Xuzhen Cao, Xiaolin Li, Liang Bai, Zhaoxin Liang, Li-Chen Zhao, and Ying Hu

Nonlinear interaction enables topological phenomena impossible in linear systems. A paradigm is a nonlinear Thouless pump, where the transport of solitons can be topologically quantized even when band occupation is nonuniform. Such nonlinear quantization traditionally requires a time-periodic Hamilt…

[Phys. Rev. B 114, L020303] Published Tue Jul 14, 2026

arXiv:2410.10031v2 Announce Type: replace-cross Abstract: We study weak symmetry-protected topological phases (SPTs) in the presence of short-range interactions. By comparing homotopical free and interacting classifications of these SPTs, we predict their stability under interactions as well as identify potential intrinsically-interacting phases. We mathematically compute the groups of weak phases in dimensions zero through three for all tenfold-way symmetry types using homotopy theory; specifically, we use Atiyah's Real $\mathit{KR}$-theory and the low-energy invertible field theory ansatz of Freed--Hopkins for the free and interacting cases, resp. Our computational techniques involve T-duality, which relates $K$-theory of the spatial torus with $K$-theory of the Brillouin torus, and a binomial formula for computing generalized cohomology of a torus. Our results carry potential implications for theoretical and experimental studies of weak phases.

Fermion bound states in the core of a line-shaped vortex of a two-dimensional topological superconductor are investigated. The superconducting pairing potential, described in terms of elliptical coordinates, vanishes along a line defect with the two foci at the endpoints. The superconductivity is induced into a topological insulator via proximity effect with a type II s-wave superconductor. The spin and the momentum are perpendicularly locked by the strong spin-orbit coupling via Rashba interaction. A zero-energy Majorana state arises from the Berry phase together with a sequence of equally spaced fermion exitations. By solving the Bogoliubov-de Gennes equations using the method employed by Caroli, de Gennes and Matricon we calculate the energies, the wave-functions and spin-polarization of the bound states. An analytic expression for the local density of states within the vortex is obtained.

We present a two-stage inverse design procedure for producing disordered stealthy hyperuniform trivalent photonic networks in two dimensions with isotropic complete photonic band gaps (PBGs) blocking light regardless of direction or polarization (TE or TM) over a wide frequency range. Most ordinary disordered systems fail to maintain complete PBGs as system size increases. The only known exceptions that remain open in the largest simulations have been generated by mapping stealthy hyperuniform point patterns into trivalent networks. However, the resulting networks are not truly stealthy hyperuniform two-phase media. Although their PBGs remain open, they are relatively narrow due to limited overlap between the TE and TM band gaps and broad band tails caused by localized defect states. By contrast, our two-stage inverse design aims to make the final network itself stealthy hyperuniform, achieving unprecedented near-optimal overlap between the TE and TM band gaps and a small defect state density at the band edges. We obtain not only single realizations with large PBGs, but a striking homogeneity across a large ensemble, effectively probing a network with 100,000 vertices. This ensemble-based band gap is comparable in width to the complete PBG of an anisotropic honeycomb photonic crystal with the same network parameters and nearly an order of magnitude wider than the previously widest known isotropic complete PBGs. Our designs can be fabricated using additive manufacturing, offering new pathways to manipulate electromagnetic waves for photonic technologies.

While synchronization has been well-studied in deterministic oscillators, most underlying oscillators are stochastic in both natural and man-made systems. Yet, the effects of intrinsic stochasticity remain poorly understood. Here, we develop a new mechanism for synchronizing circadian KaiC molecules that have topologically protected cycles. We find a phase transition to synchronization that depends only on the single-oscillator coherence, across a range of molecular changes that determine this coherence. Examining both mesoscopic and macroscopic numbers relevant for cellular and in vitro conditions respectively, we find different scaling properties above and below the phase transition. Our results shed light on several existing experiments and further predict that external changes can be offset by compensatory changes that improve the single-oscillator coherence - demonstrating a tunable pathway between stochastic single oscillators and their robust collective rhythms.

Advanced Functional Materials, EarlyView.

The monogamy of quantum entanglement, applied by Almheiri-Marolf-Polchinski-Sully (AMPS) to black holes, obstructs a smooth horizon vacuum after the Page time. We transcribe this argument to Hawking-like phonon radiation from a sonic horizon in the Unruh acoustic metric. An exact purity identity shows that post-Page-time unitarity forces the entanglement between an outgoing phonon and its interior partner to vanish, selecting a non-Hadamard (Boulware-like) phonon state, which we define as an acoustic firewall. Its renormalized stress tensor differs from the smooth state by a constant, negative near-horizon flux, and the thermal-atmosphere energy density it removes, measured by a static calorimeter, grows as $(\delta r)^{-2}$ in the radial coordinate toward the horizon (singular in the free-fall frame), cut off at the healing length. The construction is kinematic and does not resolve the information paradox; it yields one concrete, falsifiable prediction: a differential phonon-calorimetry signal $\mathcal{R}(\delta r)=|\Delta\mathcal{E}|/\mathcal{E}^{(0)}\to(\ell_\kappa/\delta r)^{2}$, present only after the analogue Page time in a Bose-Einstein condensate.

Author(s): Vimalesh Kumar Vimal and Jorge Cayao

Minimal Kitaev chains host Majorana quasiparticles, which, although not topologically protected, exhibit spatial nonlocality and hence are expected to be useful for quantum information tasks. In this work, we consider two- and three-site Kitaev chains and investigate the dynamics of bipartite and mu…

[Phys. Rev. B 114, 034308] Published Tue Jul 14, 2026

Communications Physics, Published online: 14 July 2026; doi:10.1038/s42005-026-02729-x

Quantum many-body systems with symmetries acting on extended objects host exotic phases that are difficult to simulate. We develop a pull-through tensor-network framework that embeds 1-form symmetries in projected entangled-pair states, enabling symmetry-resolved optimization and diagnostics of topologically ordered states.

Nature Reviews Physics, Published online: 15 July 2026; doi:10.1038/s42254-026-00963-4

Students need to experience quantum hardware beyond cloud access to learn how an ideal circuit becomes a physical measurement. Universities should therefore procure teachable systems, not showroom machines.

Author(s): Qing-Feng Xue, Qi Zhang, Xu-Cai Zhuang, Ying-Jie Zhang, Yun-Jie Xia, Enrico Russo, Giulio Chiribella, Rosario Lo Franco, and Zhong-Xiao Man

The principle that heat spontaneously flows from higher temperatures to lower temperatures is a cornerstone of classical thermodynamics. While this principle holds true for macroscopic systems at equilibrium, here we show that, when a quantum system undergoes two thermalization processes in an indef…

[Phys. Rev. Lett. 137, 030404] Published Tue Jul 14, 2026

Advanced Science, EarlyView.