Papers

Single-Molecule Magnets (SMMs) exhibit slow magnetic relaxation as a result of axial magnetic anisotropy inhibiting spin-phonon transitions. In order to establish a direct link between physical observables and the microscopic theory of magnetic relaxation, we here develop and numerically implement a first-principles linear-response theory for open quantum systems that provides access to the complex a.c. magnetic susceptibility in the presence of an oscillating a.c. magnetic field. Once combined with density functional theory and multiconfigurational electronic structure simulations, this formalism is applied in a fully first-principles fashion to three cyanido-bridged Ln/Y-based coordination polymers with general formula {Ln$^{III}_x$ Y$^{III}_{1-x}$ [Co(CN)$_6$]}, where Ln = Yb (1), Tb (2), and Dy (3). The method is able to reproduce the low-temperature direct relaxation process and its field dependence, as well as the high-temperature Orbach relaxation regime for all the investigated compounds. These results demonstrate the feasibility of ab initio simulations of magnetic a.c.susceptibility in lanthanide-based SMMs and support the potential of further development of ab initio open quantum systems methods towards the completion of a magnetization dynamics theory.

Understanding and manipulating nanoscale domain wall (DW) dynamics is a central topic in magnetism and spintronics for its promising applications in logic and memory devices. In most magnetic systems, inertia affects only transient DW dynamics, while the long-time DW motion is uniquely determined by the magnitude and direction of the applied current. Here we show that this paradigm breaks down in ferrimagnets near the angular momentum compensation point. We demonstrate that a DW can propagate steadily either forward or backward even under a direct current, with the direction controlled solely by the current strength. This anomalous phenomenon originates from the inertial dynamics of an internal DW collective coordinate, which behaves as a massive object evolving in a current-dependent double-well potential. Depending on the driving current, the system relaxes into distinct stable states associated with opposite directions of motion. Our findings reveal an unexpected role of inertia in nonlinear spin dynamics, and enable low-energy spintronic functionalities including sensitive magnetic-field detection and reconfigurable one-port devices.

Relaxation phenomena far from thermal equilibrium feature a rich phenomenology, including the thermal relaxation asymmetry. The latter states that heating occurs faster than cooling in overdamped harmonic systems quantified in terms of excess free energy and entropy production. Upon isolating the relevant relaxational contribution to the entropy production, we here algebraically prove the asymmetry in thermal relaxation in phase space in the entire range from overdamped dynamics to underdamped dynamics. We show that for the same setup as for overdamped dynamics (i.e., motion in harmonic potentials, also known as Ornstein-Uhlenbeck dynamics), even in the more general case of phase-space relaxation, i.e., underdamped dynamics, far-from-equilibrium heating is faster than cooling. The coupling of positions and velocities emerging in this generalization further underscores, in a striking manner, the intricate dynamics of such thermal relaxation processes that do not pass through local equilibria. Investigating the overdamped limit, our generalized approach reveals, interestingly, that an excess free energy contribution from the velocity degrees of freedom does not trivially vanish in the overdamped limit, but is instead affected by the precise interpretation of temperature quenches in overdamped systems.

Among wurtzite-type ferroelectrics, scandium-doped aluminum nitride (ScAlN) has emerged as a leading candidate for CMOS-compatible low-voltage memory, combining strong spontaneous polarization with process compatibility. A remarkable feature of this system is the pronounced reduction of the coercive field (Ec) with increasing Sc concentration; however, its microscopic origin remains poorly understood at the atomic scale, particularly under finite temperature and applied electric fields. Here, we integrate a density-functional-theory-accurate machine-learning force field with an equivariant neural-network-based Born effective charge model to perform large-scale electric-field-driven molecular dynamics simulations at near-first-principles accuracy. The framework correctly reproduces the experimentally observed qualitative trends in key experimental trends, including the decrease in the c/a ratio and the monotonic reduction of Ec with increasing Sc content. Beyond static structural softening, we uncover a dynamic mechanism underlying Ec reduction. Sc atoms exhibit larger thermal vibrations and undergo preceding displacements during switching, acting as dynamic triggers for polarization reversal. Moreover, the displacement correlation between Sc and Al atoms evolves systematically with composition, enhancing cooperative atomic rearrangements and lowering the effective switching barrier. These results demonstrate that Ec reduction in ScAlN arises from the synergy of structural softening and dynamic correlation evolution, providing a new perspective for designing hexagonal ferroelectrics.

Using computer simulations and theory, we investigate the ultrasoft interactions between dendrimers formed of a central polymer connected by stiff linkers to a corona of flexible polymers, forming `pompoms' at the ends of the linkers. We show that the resulting coarse-grained interaction potential between pairs of dendrimers exhibits tunable lengthscale competition based on properties of the core and corona polymers. We present a simple model for this pair potential, which we confirm using accelerated Monte Carlo methods. We then demonstrate the connection between dendrimer structure and mesoscopic phases by presenting parameter choices that result in stable dodecagonal quasicrystals, and show that the size of the region in the phase diagram where quasicrystals are stable can be controlled by tuning details of the polymer architecture alone. These results pave the way for experimental realization of soft matter quasicrystals by identifying what overall molecular architecture leads to their stability.

The anisotropic spin splitting in unconventional magnets opens new opportunities for realizing spintronic functionalities without relying on net magnetization or relativistic spin-orbit coupling. Here, we propose a spin valve and a spin transistor based on unconventional $p$-wave magnets (UPMs). The spin valve is realized in a junction where a normal metal is sandwiched between two UPMs whose exchange-field strength vectors are oriented transverse to the junction direction. The conductance of such a device is governed by the spin alignment between two UPMs: when their strength vectors are parallel, the spin-state alignment enables efficient electron transmission, leading to a high-conductance state; in contrast, the antiparallel configuration suppresses the conductance owing to the opposite spin orientations. Furthermore, the spin-valve can be extended to a spin transistor by replacing the central normal metal with another UPM with a longitudinally oriented strength vector and a perpendicular spin polarization axis. The central UPM enables uniform spin precession with the same precession frequency for all transverse modes. Both devices can be electrically controlled by modulating the strength vectors of UPMs. These findings establish UPMs as a promising platform for developing spintronic devices without net magnetization or relativistic spin-orbit coupling.

In order to investigate the crossover from the homogeneous behavior to inhomogeneous (percolative) one, the temperature $T$ and magnetic field H dependence of the sheet resistance $R_\square$ have been measured for two-dimensional granular aluminum films. Fitting the theory to data of magnetoconductance near $T_C$ with use of the diffusion constant $D(T)$ as a fitting parameter, we have obtained the anomalous $T$-dependent diffusion constant $D$. From the analysis of $D(T)$, the electron diffusion index $\theta$, a certain critical exponent in percolation theory, has been obtained. In the relation $R_\square-\theta$, the value of $\theta$ varies abruptly near $1.5k\omega$. This behavior suggesting the above mentioned crossover is similar to our previous results determined from the temperature dependence of the upper critical field. For percolative films in $H = 5\mathrm{T}$, we have found the strong $R_\square$ dependence of the prefactor $\alpha_T$ in the expression$\sigma=[\alpha_T e^2/(2\pi^2\hbar)]\ln T+\sigma_0$. The relation $\alpha_T\propto1/R_\square$ can be explained qualitatively by a model of scaling law for percolation.

Achieving long-lived nanoscale magnetic solitons remains a central challenge, as their lifetimes typically decrease rapidly with temperature. Here, we demonstrate that anisotropic Dzyaloshinskii-Moriya interaction (aDMI) enables spatially extended saddle points (SPs) that fundamentally alter thermally activated decay. In contrast to conventional localized SPs, these extended configurations completely suppress the entropic contribution to the activation rate, rendering the lifetimes effectively temperature independent. To establish this mechanism, we develop a first-principles method based on spin spirals to compute DMI beyond the isotropic approximation, resolving its full directional dependence for arbitrary nearest neighbors. We apply this method to oxidized Fe$_3$GeTe$_2$ (FGT-O), an experimentally accessible van der Waals magnet. Oxygen adsorption simultaneously breaks inversion symmetry and lowers the in-plane crystalline symmetry, thereby generating a sizable aDMI. We demonstrate that aDMI stabilizes nanoscale antiskyrmions with energy barriers exceeding 120 meV at low external magnetic fields. Crucially, extended SPs enhance the lifetime in FGT-O by more than five orders of magnitude at room temperature compared to conventional ultrathin-film skyrmion systems. We further show that aDMI is not the only route to such extended SPs and identify the general conditions under which they emerge, establishing a general route to soliton decay pathways with temperature-independent prefactors. Our results uncover a new paradigm for enhancing soliton stability through transition-state geometry rather than energy-barrier height.

Laser induced white emission (LIWE) was thoroughly studied in recent decades. However, despite the progress in understanding of this phenomenon, the mechanism behind LIWE remains unclear. The present paper focuses on the influence of Yb content on the LIWE properties of Cr,Yb:YAG nanocrystals. Microstructure and optical properties of the samples were characterized and the influence of the concentration of Yb3+ ions on the spectroscopic properties of Cr,Yb:YAG and energy transfer processes between Cr3+ and Yb3+ ions was revealed. Multiphoton ionization theory was used to explain the findings of the paper.

We investigated the Fermi surface (FS) in the paramagnetic state of Kagome metal CsCr$_3$Sb$_5$ by employing a laser photoemission microscopy. We found a circular FS and two hexagonal FSs around the Brillouin zone (BZ) center. Polarization-dependent measurements further enable us to detect small FS pockets at the BZ boundary. According to the density functional theory calculations, the orbital characters of the FSs were determined from their shape and orientations. We found that the size of the FS is strongly modified for the d$_{xz}$ orbital, suggesting the orbital-dependent correlation effect. These results provide an electronic basis for exploring the interplay of antiferromagnetic/charge density wave order and possible unconventional superconductivity in this compound.

Bayes' rule is widely regarded as the canonical prescription for belief updating. We show, however, that one can arbitrarily preserve pre-specified beliefs while appearing to perform Bayesian updates via "prior hacking": engineering a reference prior distribution such that, for a fixed channel and evidence, the update matches a chosen target distribution. We prove that this is generically possible in both classical and quantum settings whenever Bayesian inversions are well-defined (with the Petz recovery map as the quantum analogue to Bayes' rule), and provide constructive algorithms for doing so. We further establish a duality between prior hacking and Schrödinger bridge problems (a key object in statistical physics with applications in generative modelling), yielding in the quantum setting a unique, inference-consistent selection among candidate bridges. This formally establishes the Bayes-like updating that Schrödinger bridges are performing with respect to the process as opposed to the reference prior, both in classical and quantum settings.

Laser Induced White Emission (LIWE) is the subject of research worldwide. Since its discovery, the understanding of this phenomenon has progressed successfully enough to reach industrial applications. However, a lack of understanding of the nature of this phenomenon limits its potential. This article is devoted to the study of the influence of nonradiative relaxation processes on the properties of laser induced white emission in Cr:YAG nanopowders. The concentration series of Cr:YAG nanopowders was synthetized by Pechini method. The microstructure, optical and LIWE properties were studied. The influence of chromium concentration on the number of photons involved in LIWE process (N parameter) is shown. The increase of N parameter is associated with an increase in the probability of non-radiative recombination processes with an increase of chromium concentration. A multiphoton ionization model is proposed to describe LIWE phenomenon.

Laser induced white emission (LIWE) caused by infrared laser excitation in Cr:YAG transparent ceramics was investigated. It was found that ceramics generates bright LIWE for excitation powers above a critical threshold. The LIWE was observed on the surface but not in the bulk on both sides of the sample. The vacuum conditions are required to observe LIWE. This phenomenon was discussed within the frame of Inter-Valence Charge Transfer (IVCT) mechanism in the Cr3+/Cr4+ ion pair.

Developing universal machine learning models for ab initio calculations is the frontier of materials cutting edge research in the new era of artificial intelligence. Here, we present the Deep Augment Way model (DeePAW) that is a universal machine learning (ML) model for orbital-free (OF) ab initio calculations, based on the density functional theory (DFT). DeePAW is currently the best OFDFT ML model according to the three criterions, 1) covering the largest number of elements, 2) having the widest application capability to diverse crystal structures, and 3) achieving the highest prediction accuracy without further fine-tuning. These scientific merits and innovations of DeePAW are stemmed from the novel SE(3)-equivariant double massage passing neuron networks. Besides predicting electron density distributions, DeePAW predicts formation energies of crystals as well and therefore paves an efficient avenue for multiscale materials modeling beyond conventional electronic structure calculation methods.

We investigate the emergence of topological superconductivity and Majorana zero modes in the two-dimensional electron gas formed at the LaAlO$_3$/SrTiO$_3$ (001) interface. Using a realistic multiband tight binding model that incorporates the $t_{2g}$ orbital structure together with atomic and Rashba spin-orbit couplings, we determine the topological phase diagrams for both fully two-dimensional and quasi-one-dimensional geometries. In the two-dimensional limit, we show that a finite out-of-plane magnetic-field component is required to drive a topological phase transition. In this case, the critical field is strongly band dependent, and for higher-lying bands, it is controlled by the interplay of spin and orbital Zeeman effects, as well as atomic spin-orbit coupling. Although a purely in-plane field is insufficient to induce the topological transition in a full 2D system, we demonstrate that a lateral confinement relaxes this constraint. In this case, the character of the edge modes depends sensitively on the field orientation, with out-of-plane fields producing conventional counterpropagating chiral modes and transverse in-plane fields giving rise to co-propagating antichiral modes. Finally, Majorana zero modes in LAO/STO nanowires with varying widths are analyzed. We demonstrate that subbands predominantly composed of $d_{yz/xz}$ orbitals exhibit exceptionally long localization lengths, which may preclude the observation of Majorana bound states in nanowires of typical experimental dimensions.

We investigate the non-equilibrium compression of a confined hard-sphere colloidal fluid driven by a mobile boundary within dynamical density functional theory. The system consists of a fluid confined between two parallel walls, one acting as an overdamped piston subjected to a sudden increase in external pressure. The piston motion is controlled by a mobility parameter $K$, which sets the relative timescale between mechanical driving and diffusive relaxation. By varying $K$ over several orders of magnitude, we identify a crossover from quasi-static compression to a diffusion-limited strongly driven regime. For small $K$, the system evolves close to equilibrium and the total injected work approaches the equilibrium free-energy difference. For large $K$, the piston rapidly adjusts and the dynamics becomes governed by diffusive relaxation, leading to saturation in the piston trajectory, pressure–position relation, particle currents, and center-of-mass velocity. In this regime, the injected work and entropy production are bounded, reflecting constraints imposed by diffusive transport. The maximum injected power scales linearly with $K$, while the entropy-production peak exhibits a crossover from quadratic growth to saturation, with peak times displaying $1/K$ scaling. The entropy change of the thermal bath interpolates between a reversible limit and a strongly driven dissipative regime. Finally, the evolution of configurational entropy and external potential energy reveals a dynamical decoupling between confinement and structural relaxation, including transient non-monotonic behavior. These results provide a quantitative thermodynamic characterization of boundary-driven compression.

We present a lithographic method for fabricating free-standing microparticles directly from SUEX dry-film epoxy resist. Unlike conventional SU-8 particle fabrication, which requires patterning on solid substrates followed by sacrificial-layer release, our approach eliminates substrate use entirely and produces particles with near 100% yields. The process supports a wide design space of in-plane geometries, including high-aspect-ratio and highly complex shapes. To enable large-scale particle libraries, we integrate the method with the Nazca Python library, allowing programmatic generation of tens of thousands of parametrically defined particle designs. This combination of substrate-free fabrication and automated design provides a scalable route to custom microparticles for materials science, microfluidics, and soft-matter applications.

Non-Arrhenius grain growth has been observed in a range of polycrystalline materials; however, its fundamental mechanisms, particularly whether the process is thermally activated or exhibits anti-thermally activation, remain controversial. In this study, SrTiO3 was employed as a model system to systematically investigate non-Arrhenius grain growth behavior through combined experimental and theoretical approaches, utilizing a newly developed grain growth model. The results reveal that non-Arrhenius grain growth is a thermally activated process without a definitive characteristic temperature, which is primarily controlled by the interplay between temperature-dependent factors and the temperature-independent parameters such as grain size and its distribution. Moreover, during abnormal grain growth (AGG), the non-Arrhenius behavior of grain growth primarily occurs at lower temperatures and gradually transitions to Arrhenius-type behavior as the temperature increases.

The interplay between local and itinerant electrons underpins many correlated and topological quantum states. Kagome lattices provide an ideal platform by hosting both flat (localized states) and dispersive bands (itinerant states), yet direct spectroscopic evidence of their dynamical coupling has remained elusive. Here we report the long-sought flat band resonance in the quasi-two-dimensional kagome bilayer material CsCr6Sb6. Using angle-resolved photoemission spectroscopy, transport measurements, and combined density functional theory and dynamical mean-field theory, we identify coexisting flat band doublets and dispersive bands near the Fermi energy. Upon cooling, the flat and dispersive bands exhibit a pronounced enhancement of spectral weight and hybridization, directly evidencing flat band resonance. Crucially, this emergence coincides with the onset of short-range antiferromagnetic correlations, contrasting sharply with conventional Kondo lattice behavior. Our findings demonstrate not only the long-sought flat band resonance in kagome materials, but also its unconventional correlation with magnetism.

We investigate the stochastic dynamics of quasiparticles within a gas of hard rods in one dimension for two choices of initial states: one with long-range correlations and the other without it. We derive analytical results for the phase space density correlations in the former case to complement the known results for the latter case. These results enable us to obtain explicit expressions for the mean, variance, autocorrelation and cross-correlation of individual quasiparticles, extending previous results to inhomogeneous cases. We also propose two methods for simulating an ensemble of trajectories of a quasiparticle with fixed initial position and velocity, and verify our analytical results on correlations. The long-range correlations introduce a diffusive-scale correction to the mean Euler generalized hydrodynamic equations, modifying the standard local equilibrium form, and our findings reveal that the form of the correction term depends on the long-range correlations present in the system.

In discrete models describing growing rough interfaces of the Kardar-Parisi-Zhang universality class, we examine height fluctuations at a fixed site as a function of time in the monolayer unit. For small systems, we show that it is possible to reach the stationary state. We compute the two-time autocorrelation and power spectra independently. The correlation function remains non-exponential and vanishes after a correlation time that diverges with system size. As a result, the power spectra display a lower cutoff that maintains constant power. In the nontrivial frequency regime, we observe $1/f^{\alpha}$-type scaling with the spectral exponent 5/3. Finite-size scaling reveals that the temporal correlation function follows a dynamic scaling. Our findings, supported by scaling-theoretical arguments, establish that the fluctuations are wide-sense stationary, implying applicability of the Wiener-Khinchin theorem.

Phase transitions in a modified Nishimori model, including the model considered by Kitatani, on a two-dimensional square lattice are investigated using a tensor-network-based sampling scheme. In this model, generating bond configurations is computationally demanding because of the correlated random interactions. The employed sampling method enables hierarchical and independent sampling of both bonds and spins. This approach allows high-precision calculations for system sizes up to $L=256$. The results provide clear numerical evidence that the spin-glass and ferromagnetic transitions are separated on the Nishimori line, supporting the existence of an intermediate Mattis-like spin-glass phase. This finding is consistent with the reentrant transition numerically observed in the two-dimensional Edwards-Anderson (EA) model. Furthermore, critical exponents estimated via finite-size-scaling analysis indicate that the universality class of the transitions differs from that of the standard independent and identically distributed EA model.

The criticality hypothesis posits that biological neural networks operate near a phase transition, yet within standard Gaussian mean-field theories this regime appears fragile and requires fine tuning. Here we show that heavy-tailed synaptic connectivity provides a robust alternative mechanism. By developing a dynamical mean-field theory for Cauchy-distributed couplings, we reduce the macroscopic dynamics to a one-dimensional gradient flow with a global Lyapunov potential. The resulting theory exhibits a continuous phase transition in which collective activity grows with the square root of the distance to criticality, and static susceptibility diverges only as the square root rather than linearly as in Gaussian mean-field theories. This structure gives rise to an emergent automatic gain control: activity-dependent noise fluctuations suppress the effective gain at high activity levels while preserving high susceptibility near the critical point. Extending this mechanism to general symmetric $\alpha$-stable inputs, we identify heavy-tailed synapses as a key microscopic origin of robust near-critical dynamics in disordered neural circuits.

Colloidal dispersions are widely found in systems ranging from natural environments to industrial materials. Their macroscopic properties such as viscosity and light scattering depend on their dispersibility, which is characterized by interparticle interactions. Osmotic pressure is induced in a solution with a concentration gradient, in which dispersity is one of the major factors governing the behavior of solutes. Thus, examining the relationship between the interparticle interactions and osmotic pressure may reveal colloidal dispersive properties. Although measuring the osmotic pressure is useful to understand dispersion systems, osmotic pressure is usually extremely low, and only limited experimental methods are available. In this study, we demonstrate that both osmotic pressure and interparticle interactions can be measured within the same experimental system, an optical tweezer system. The directly measured pressure is consistent with both the Brownian dynamics simulation and theoretical results based on the effective hard-sphere model, both of which were calculated using the interparticle interactions directly measured in the experiment. This agreement demonstrates the applicability of the proposed technique for investigating dispersive properties based on particle-level interactions. The proposed technique enables bottom-up design of colloidal materials through particle-level modifications.

Photonic computing using chalcogenide phase-change materials (PCMs) is under active development for energy-efficient artificial intelligence (AI) applications. A key requirement is to enable as many optically programmable levels per device as possible, while maintaining relatively low optical loss. In this work, we carry out multiscale simulations using density functional theory and finite-difference time-domain methods, proposing a "the shorter the better" strategy to optimize the performance of Sb2Te photonic waveguide devices. Our subsequent experimental characterizations of Sb2Te thin films and optical device measurements fully verify our theoretical predictions. In particular, we reveal the unconventional optical properties of metastable crystalline Sb2Te, and utilize these features for device design, yielding a simultaneous improvement in both the programming window and the optical loss. Overall, an optical programming precision exceeding 7-bit is achieved using a single waveguide cell, setting a new record for all-optical phase-change memory devices. Our work serves as a compelling example of computational material design, which demonstrates the predictive power of multiscale simulations in guiding the design of phase-change photonic devices for enhanced performance.

Identifying materials hosting an excitonic insulator ground state has been one of the major pursuits in condensed matter physics in recent years. Promising candidates in transition metal chalcogenide compounds (TMC), including $1T-\mathrm{TiSe_2}$, $\mathrm{Ta_2Pd_3Te_5}$, and $\mathrm{Ta_2NiSe_5}$, share a crucial common characteristic: their low-energy physics is governed by electrons in $d-$ orbitals subject to strong on-site Coulomb interactions. In this work, we investigate spatially indirect exciton condensation in two-dimensional semimetals on triangular lattice. Using a combination of dynamical mean-field theory and the determinant quantum Monte Carlo method, we study two- and three-orbital Hubbard models incorporating strong on-site ($U$) and inter-orbital interactions ($V$). Our results demonstrate that on-site Hubbard $U$ can strongly suppress the condensation temperature $T_c$, an effect that is particularly pronounced at higher electron-hole pair densities. This behavior contrasts sharply with the case without on-site $U$, where $T_c$ grows with pair density at fixed $V$. Moreover, we uncover competition among multiple electron-hole pairing channels in the three-orbital model, which also acts to suppress $T_c$ of exciton condensation. An orbital-selective electron-hole pairing state is identified. These findings may help explain the large discrepancy between strong binding-energy and relative low transition temperature for indirect excitons in TMCs materials, offering important insights for understanding and engineering exciton condensation in materials with strongly correlated $d-$ shell electrons.

Graph-theoretic topological frustration is a peculiar situation on a finite piece of the honeycomb lattice that prevents a full pairwise coupling of the lattice sites via nearest neighbor links, even when the total number of sites is an even number and the structure possesses no sublattice imbalance. This type of frustration is inherent for organic molecules that are classified as concealed non-Kekulean hydrocarbons, representing peculiar diradicals. Here we show that this topological frustration persists in two-dimensional systems based on the honeycomb lattice. Such systems exhibit fully flat electronic energy bands located at the Fermi level. Therefore, two-dimensional ultimately flat bands can be systematically and predictably constructed for graphene monolayer nanomeshes. These systems are prone to antiferromagnetic ordering and hybrid spin-wave excitations mixing weak ferromagnetic and strong antiferromagnetic features, which could pave the way towards low-power, compact, and ultrafast organic spintronics with near room-temperature operation.

The utility of non functionalized poly(N-isopropylacrylamide) (pNIPAM) microgels in physiological and environmental applications is strictly dependent on their reversible thermoresponsiveness and stability in saline media. Despite their importance, a unified understanding of how network topology specifically crosslinker concentration and distribution regulates ionic sensitivity remains fragmented in the literature. This work systematically investigates the interplay between network topology and ionic strength (0 to 100 mM NaCl) across eight distinct microgel architectures, ranging from ultra-low crosslinked (ULC) to core-corona and homogeneously crosslinked (HC) variants. Utilizing dynamic light scattering across 22 batches, we analyzed critical thermoresponsive properties, including volume phase transition temperature (VPTT) shifts, salt tolerance thresholds, hysteresis indices, and flocculation kinetics (only at extreme salinity, 1000 mM NaCl and at 25 deg C). This comprehensive investigation enables a multidimensional analysis of how ionic strength, the presence or absence of crosslinkers (MBA), spatial crosslinking distribution, and thermodynamic states dictate microgel behavior across varying temperatures. Finally, we evaluate the applicability of this experimental library to established theoretical frameworks, specifically the Flory Rehner and Flory Rehner Donnan models, addressing ongoing debates regarding their validity in describing complex microgel systems.

Unraveling the hierarchical structure-property relationships is the central challenge of materials science, necessitating the interpretation of data across vast physical scales from micro to macro. Despite the rapid integration of Large Multimodal Models (LMMs) into scientific workflows, existing scientific benchmarks primarily focus on general chart interpretation or isolated common-sense reasoning, failing to capture reasoning ability across intricate physical dimensions. To address this, we introduce CSMBench, a dataset comprising 1,041 high-quality figures curated from premier journals up to September 2025. CSMBench categorizes data into four scientifically distinct regimes: atomic, micro, meso, and macro scales, strictly aligning with the focus and definitions in materials study. Through open-ended figure description and multiple-choice caption matching tasks, we evaluate state-of-the-art open-source and closed-source models. Our analysis identifies that performance varies significantly across physical scales due to the distinct visual characteristics, highlighting the limitations of current generalist models and identifying critical directions for achieving hierarchical and accurate understanding in materials research. The CSMBench is publicly released at: https://huggingface.co/datasets/lututu/CSMBench.

Multiple pairs of bronze pieces were joined along a common seam and then exposed to Nb vapor via sputter deposition during heating at $\sim$715 $^\circ$C to form a diffusion bond between the pieces. Polishing and alignment of the pieces created smooth surfaces normal to the Nb flux with seams perpendicular to the surface (i.e. parallel to the Nb flux). Conversion of Nb to Nb$_3$Sn took place simultaneously with diffusion bonding, resulting in Nb$_3$Sn thin films that coated bronze surfaces and spanned seams with uniform thickness. Characterization of superconducting properties via magneto-optical imaging suggests that supercurrent flows freely across the seam in several examples when cooled to 9 K and shielding or trapping low magnetic field. Modification of the process to coat the pieces with Nb prior to diffusion bonding and Nb$_3$Sn formation resulted in varying degrees of seam coverage by the resultant Nb$_3$Sn films. The pre-coating method did not produce any example with quality comparable to the examples obtained by the hot bronze approach. This work could enable new approaches to joining Nb$_3$Sn materials in magnet conductor and RF cavity applications.