Disorder in magnetic materials prevents reliable control of spin textures and constrains their integration into spintronic devices. Existing methods access disorder only indirectly through external imaging probes or bulk transport measurements, leaving the internal energy landscape inaccessible. We introduce an intrinsic magnetic microscopy method in which a topological spin texture serves as a mobile probe of disorder, directly mapping energy landscapes inside multilayer devices without probe-sample separation. Using a ~10-nm magnetic vortex core confined within a magnetic tunnel junction, we track its displacement with nanometer-scale sensitivity to resolve intrinsic and engineered defect-induced potentials and directly quantify local pinning forces. This framework establishes spin textures as internal spectroscopic probes of disorder and enables quantitative engineering of pinning structures in functional magnetic systems.

This paper reports on progress in cryogenic magnetic field sensing using vortex magnetic tunnel junctions (MTJs) at T < 10 K. The MTJ magnetoresistive signal is amplified using a wire-bonded foundry-fabricated 180 nmprocess cryo-CMOS sense amplifier, providing similar to 100 mG single-shot detectivity. Functional MTJ sensor deposition results on a true CMOS surface with fill exclusion are also presented. The aim is to make a magnetic field camera for tracking flux vortex motion in superconducting films, leading to optimized VLSI superconducting electronic (SCE) circuitry.

The intrinsic mechanisms linking process parameters, microstructure, and performance for laser powder bed melting (LPBF) formed AlMgScZr alloys remain to be elucidated. A multi-scale linkage framework is established, encompassing the full process chain from volume energy density (VED), to pore defect and microstructure regulation through heat flux parameters, and ultimately to macroscopic performance. The specific contributions of each strengthening mechanism are quantified, validating the effectiveness of the framework. The results show that within VED of 60-80 J/mm3, an optimal balance between pore nucleation, growth, and degassing achieves a relative density of 99%. The nucleation of spherical pore remains unavoidable, affected by heterogeneous catalysis of Al3(Sc,Zr). Grains evolution is synergistically regulated by thermodynamic parameters of solidification, catalytic nucleation of nanoparticles and intense shear stress. Coarse grains refine to 2.10 & micro;m at VED of 97.2 J/mm3, due to fluid-induced strong shear stress and shifting solidification mode toward fine grains. Refinement promotes dislocation recovery, weakening texture intensity. Microhardness peaks within VED of 60-80 J/mm3, owing to the defect suppression, grain regulation, and Al3(Sc,Zr) formation. The theoretically calculated strength agrees well with experiment (501 MPa), with a 3.3% error. These results provide theoretical guidance for high-quality LPBF fabrication of AlMgScZr alloys.

Two-dimensional (2D) multifunctional materials with distinctive features such as magnetic, ferroelectric, piezoelectric, and optical property are in high demand due to their potential applications in novel nanoscale devices. Herein, based on first-principles calculations, we present a family of 2D multiferroic MoNX2 (X = F, Cl, Br, I) materials. Among them, MoNF2 is an anti-ferroelectric (AFE) ferromagnetic (FM) semiconductor with Curie temperature (TC) of 497 K. MoNX2 (X = Cl, Br) are ferroelectric (FE) antiferromagnetic (AFM) semiconductors. All of them exhibit an in-plane spontaneous electric polarization of up to 260 pC m-1 and piezoelectric response. The FE switching energy barrier is no more than 0.1 eV per atom for them. Additionally, they exhibit strong linear optical dichroism and hyperbolicity in the visible light region. The alignments of the band edges of MoNX2 (X = Cl, Br, I) with the redox potentials of water show that these materials are suitable for use as photocatalysts for water splitting. Their intriguing magnetic, electronic, ferroelectric, piezoelectric and optical properties render them ideal for use in high-performance, multifunctional applications.

Magnetic tunnel junction (MTJ) sensors are attractive for detecting extremely small magnetic fields, yet their performance is often quantified using sensitivities derived from major loops or larger-field minor loops which inherently include hysteretic contributions. As a result, these conventional metrics significantly overestimate detectability by including irreversible processes that vanish in the small-field limit. Here, we systematically measure the low-field response of uniaxial MTJs under both ac and dc magnetic excitation and demonstrate a distinct transition from hysteretic to fully reversible behavior as the field amplitude is reduced. By adapting the Jiles-Atherton model to analyze MTJ conductance, we establish a unified framework that captures magnetization processes down to nanotesla range, yielding quantitative parameters that resolve reversible and irreversible dynamics with excellent fidelity. In the reversible regime, the sensitivity converges to a constant value of 0.55%Oe -1, defining an intrinsic, history-independent response of the MTJ. Importantly, this is less than half of the 1.2%Oe -1 obtained from higher-field minor loop estimates but is physically representative of the sensing response in low-field operation. The constant and intrinsic sensitivity corresponds to the true value of detectability, confirmed by noise spectral density measurements under low-field ac excitation. These results establish a quantitative framework for MTJ evaluation that emphasizes intrinsic, hysteresis-free performance, providing both a realistic basis for calculating field detectability and a general methodology for probing magnetization in micron- and nano-scale ferromagnets.

The laser powder bed fusion (LPBF) process for AlMgScZr alloy production generates residual stresses and anisotropy, which can affect dimensional stability and fatigue reliability of aerospace components. A thermomechanical coupling model of multi-layer and multi-track, integrating dynamic phase change control, hierarchical activation technology, and temperature-dependent elastoplastic constitutive, was developed to investigate the evolution of residual stress anisotropy. The microscopic effects of the unique microstructure in the AlMgScZr alloy on residual stress and its anisotropy were investigated, and a process optimization strategy was proposed. The results show that the model can effectively predict residual stress with average error of 11.83%. The model accurately captures residual stress cyclic features of "formation-relaxation-reformation" induced by in-situ reheating. The top layer shows high residual stress and its anisotropy relative to low layer, due to in-situ preheating and reheating effect. The bimodal grain structure of LPBF formed AlMgScZr alloy alleviates residual stress anisotropy by cooperatively regulating elastic and plastic responses. A process optimization strategy, based on in-situ preheating and reheating effect, was proposed to obtain process windows (laser power 280-320 W, scanning speed 1.0-1.2 m/s, and hatch spacing of 130-140 mu m). This research provides guidance for mitigation of residual stress and its anisotropy in LPBF formed AlMgScZr alloys.

We propose an oscillation-controlled magnetic sensing (OCMS) circuit architecture using MgO-based magnetic tunnel junctions (MTJs) and investigate its magnetic field response characteristics. Compared to the conventional sensing-current method commonly used in hard disk drive (HDD) read heads and magnetic sensors, the OCMS approach achieves an output voltage up to 8.1 times higher. Notably, a large oscillation output of 952 mV(pp) is obtained with sensing current as low as 0.4-0.6 mA flowing through the MTJ. The measured output response shows strong agreement with the TopSPICE simulations, which further predict output voltages exceeding 10 V-pp at a sensing current of 0.82 mA and an operation frequency of 10 MHz. These results demonstrate that the OCMS method enables high-output, low-power, and high-frequency magnetic sensing, offering a promising solution for the next-generation spintronic sensor technologies.

Uniaxial and vortex-state magnetic tunnel junction (MTJ) sensors represent two widely used device configurations for magnetic field detection. Uniaxial sensors remain the prevalent design due to their high sensitivity and straightforward operation, while vortex-state sensors are gaining popularity for their intrinsic non-hysteretic response to external perturbations. Each architecture offers distinct advantages and trade-offs, yet their relative performance under cryogenic conditions has not been systematically characterized. Such knowledge is essential for emerging low-temperature applications, particularly in quantum device metrology and superconducting electronics. In this work, we report the first systematic temperature-dependent comparison of uniaxial and vortex-state MTJ sensors over 10-300 K. In addition to the parallel, antiparallel, and zero-field conductance states, we extract the low-field sensitivity as a function of temperature. Both sensor types exhibit a pronounced increase in their overall tunnel magnetoresistance (TMR) ratio at low temperatures. However, uniaxial MTJs show a 17% reduction in the zero-field sensitivity, driven by a more than twofold rise in coercivity. In contrast, vortex-state MTJs exhibit a nearly constant sensing response over the entire temperature range, showing only a 7% increase of sensitivity at 10 K from 300 K. Additionally, the vortex-state MTJ achieves a temperature coefficient of sensitivity of -376 ppm K-1 at room temperature and -21 ppm K-1 at low temperatures, indicating highly stable and enhanced performance in cryogenic regimes. These results demonstrate that TMR alone does not govern sensing performance and underscore the decisive role of magnetization reversal dynamics and device geometry. Vortex-state MTJs thus emerge as robust candidates for cryogenic sensing applications requiring thermally stable and reliable field detection with diminished hysteresis.

Magnetic-annealing-induced uniaxial anisotropy is shown to influence vortex formation in magnetic tunnel junction (MTJ) free layers of various diameters, with micromagnetic simulations demonstrating a threshold for single-vortex formation that exhibits an inverse diameter dependence. Angular M-H curves were measured for MTJ multilayers under different annealing conditions, and reveal that a two-step orthogonal magnetic annealing process reduces the uniaxial anisotropy in the free layer from 1040J/m3 to 130J/m3. This reduction in anisotropy allows for vortex formation in MTJ sensors as large as 40μm. Increasing the MTJ diameter leads to an enhancement of magnetic sensitivity up to 2.80%/Oe with the conventional definition, or 1.78%/Oe via an ac sensitivity measurement that verifies the nonhysteretic response. This result demonstrates an eightfold increase in vortex-MTJ sensitivity, compared with standard MTJs that have diameters limited to 5 μm, and this work provides the foundation for highly sensitive vortex-MTJ-based sensors for applications that require a nonhysteretic, ultrasensitive response.

Two-dimensional (2D) multiferroic materials have attracted great interest owing to the integration of ferroelastic and ferromagnetic properties. We identify a novel 2D multiferroic vanadium dioxide (VO2) monolayer exhibiting a monoclinic phase with a C 2/ m space group using density functional theory (DFT) calculations. The energetic, dynamic, thermodynamic and mechanical analyses indicate that the monolayer exhibits excellent stability and can be prepared experimentally. The arrangement of the electronic energy bands is analogous to that of a type I heterostructure. The electron doping at a concentration of 0.2 electrons per V atom results in a significant increase in the Curie temperature (TC) C ) from 11.2 to 184 K estimated by Monte Carlo simulations, and a transition from semiconductor to half-metallicity. In addition, the VO2 monolayer exhibits 120 degrees degrees ferroelastic switching with a moderate switching energy barrier of 32 meV per atom, subsequently allowing 120 degrees degrees rotation of the easy magnetisation axis. Our work reveals the intrinsic multiferroicity of VO2, which may provide a guidance on the design of next-generation mechanical/spintronic devices.

To develop high-performance soft magnetic flux concentrator (MFC) materials, which are crucial for amplifying magnetic fields through the enhancement of local magnetic flux density, two ferromagnetic alloys, Co88Zr4Nb8 (CZN) and Fe73.5Si15.5B7Nb3Cu1 (Finemet®), were investigated. Thin films with thicknesses ranging from 100 to 1200 nm were deposited by magnetron sputtering and annealed at various temperatures. CZN demonstrated optimal soft magnetic properties in its as-grown amorphous configuration. In contrast, annealing significantly improved Finemet's performance between 200°C and 500°C, where its nanocrystalline structure yielded ultra- soft behaviour. Additionally, thickness dependence revealed distinct trends in magnetic behaviour for both materials. For CZN, magnetic softness was best achieved at a larger thickness (1200 nm), while for Finemet, an optimum was observed at an intermediate thickness (800 nm). Thus, CZN is suited for cases where annealing is impractical, such as CMOS-compatible or MEMS-integrated sensors, as its properties are optimised without further processing, particularly in thicker films. Finemet, however, requires controlled annealing to obtain soft magnetic behaviour, making it suitable for applications that demand maximum permeability and can tolerate higher temperatures. Both materials demonstrate excellent potential for MFC integration in magnetic sensing and spintronic platforms. The optimal choice, however, depends on the thermal budget, processing conditions, and the performance metrics prioritised in the target application.

The performance of proton exchange membrane fuel cells (PEMFCs) is greatly affected by their operating parameters, especially at high current densities. An advanced concentration loss model is proposed to improve a semi-empirical model describing PEMFC polarization, with the aim of accurate prediction at the whole current density interval from low to high levels. Experiments are designed to verify the improved semi-empirical model. Model comparison shows that the improved semi-empirical model has a better prediction accuracy and generalization ability than others. The effects of operating parameters and structural parameters on PEMFC performance are analyzed. The results indicate that a relatively high operating temperature, pressure, and gas diffusion layer (GDL) porosity can increase PEMFC performance. The influence of relative humidity and PEM thickness on PEMFC performance is different at low and high current densities. A relatively high humidity can improve PEMFC performance at a low current density, but PEMFC performance will be reduced if the relative humidity is too high at a high current density. A thinner PEM thickness can improve PEMFC performance at a low current density, but PEMFC performance does not necessarily improve with a decreasing PEM thickness at a high current density. Overall, the improved semi-empirical model realizes an accurate analysis of PEMFC performance from a low to high current density.

As with altermagnetism, the theoretical prediction of fully compensated ferrimagnetism, which exhibits band spin splitting yet has a zero net magnetization, has yet to be validated experimentally. In this work, a new class of Luttinger-compensated ferrimagnetic semimetals, Mn2NX (X = F and Cl) monolayers, have been identified theoretically through first-principles calculations. They are dynamically, thermally, and mechanically stable. Magnetic ions with opposite spin lattices cannot be connected by any symmetry. Consequently, the bands exhibit spin-splitting, yet the total magnetic moment remains zero. Mn2NX systems exhibit a Néel temperature (TN) approaching room temperature, in-plane auxiticity, and anisotropic ultrafast Fermi velocities. Furthermore, Mn2NX materials exhibit ferroelasticity with moderate switching barriers and low reversible strain. The in-plane anisotropic properties are modulated by the 90° ferroelastic transition. Our work enriches Luttinger-compensated ferrimagnetic materials, providing an ideal opportunity to examine their unique physical properties and potential applications in spintronic devices.

Two-dimensional semi-metallic Luttinger compensated magnetic materials Mn 2 NX (X = F, Cl) with ferroelasticity are predicted via first-principles calculations.

Photoelectron satellites-the structures appearing on the low kinetic or high binding-energy side of the "main" or "elastic" photopeak-betray the complex many-body interactions set in motion by the sudden creation of the core hole. In this work, we demonstrate, using the technologically important ferromagnetic half-metal CrO2, how such satellites can manifest themselves in other core-level spectroscopies of the material and how they can reveal important details pertinent to its electronic structure. Specifically, we identify a fluorescence satellite in the Cr L3 resonant x-ray-emission spectra that radiates at a constant emission energy across the Cr L3 x-ray edge with energy approximate to 1.3 eV above the ordinary valence fluorescence. We provide evidence that this feature arises from the valence recombination of the Cr 2p core hole "dressed" by the same shakeup charge-transfer process present in both the Cr x-ray photoelectron and the Cr x-ray absorption spectra with its energy uniquely measuring the exchange splitting of the Cr 3d level. Further analysis of the x-ray emission data reveals three additional features that radiate at constant loss energy that are attributed to combinations of Cr 3d(t2g)-* Cr 3d(t2g), charge-transfer O 2p-* Cr 3d, and crystal-field Cr3d(t2g)-* Cr3d(eg) excitations. These assignments and their energies are supported by density-functional theory calculations, the accuracy of which we demonstrate by hard x-ray valence-photoemission measurements. Atomic multiplet calculations, which include crystal-field effects, help interpret x-ray photoelectron and x-ray absorption spectra of the covalently mixed Cr ion. Resonant Cr K-L2,3L2,3 Auger-electron emission spectra support a ligand-to-metal nature of the charge-transfer process while highlighting the charge sensitivity differences between photon-in/electron-out and photon-in/photon-out spectroscopies.

Capacitive deionization (CDI) holds strong potential for water reuse and low-energy desalination due to its environmental and operational advantages. Accurate modeling of CDI systems requires integration of experimental data that reflect real electrochemical behavior. However, existing models often neglect key electrode and interfacial parameters, limiting their ability to capture dynamic coupling among electric fields, ion transport, and charge storage. To address this, this study proposed a Variable Resistance EIS-based (VRE) model for mass transfer kinetic modeling, which is developed based on parameters fitted from electrochemical impedance spectroscopy (EIS). Key equivalent circuit elements such as series resistance, charge transfer resistance, and double-layer capacitance are extracted from EIS measurements to construct a physically constrained dynamic equivalent circuit model. This model is embedded within a multiphysics framework to resolve electric field distribution, ion migration, and fluid transport in a coupled manner. A concentration-dependent correction for electrolyte conductivity is further introduced to reflect the evolving electrode behavior during CDI operation, enhancing the model physical reliability and predictive accuracy. Validation under various operating conditions and CDI modes confirms that the model accurately captures the effects of influent concentration, electrode size, and flow rate, and reproduces system responses under constant current charging and recirculating flow. This method outperforms conventional empirical models in both theoretical rigor and engineering applicability, offering a robust tool for CDI system design and optimization.

We present a study of the low-temperature, high-field magnetotransport behavior of epitaxially grown CrO2 thin films on (100) TiO2 substrates. Electron transport measurements confirm high sample quality, with a residual resistivity ratio as large as 45. A logarithmic fit of the low-temperature regime yields a T 4.5 power law, indicative of the elusive double-magnon scattering in half-metallic ferromagnets. Angle-dependent anisotropic magnetoresistance (AMR) measurements reveal a large projected density of states along [001] with a maximum AMR value of 2.4%. Pronounced, axis-dependent Shubnikov-de Haas (SdH) oscillations are observed in the longitudinal magnetoresistance (MR), with discrete Landau levels mapped at various tilt angles of the magnetic field. Their angular dependence follows a 1/ cos theta relation pointing to a highly anisotropic Fermi surface, and amplitude scaling adheres closely to the thermodynamic Lifshitz-Kosevich formalism. The out-of-plane MR reaches 6.58%, the largest reported for CrO2 thin films. Notably, this study presents an observation of SdH oscillations in a half-metallic oxide with near-perfect spin polarization, a significant advancement in the field of spintronics.

Emergent inductance has attracted significant interest for its relevance in both interesting fundamental physics and practical applications in magnetic devices that demand miniaturization without compromising inductance. In this Letter, we report the discovery of a stepwise magnetic field-induced emergent magneto-inductance (EML) effect in Permalloy (Py) thin films deposited on polycarbonate (PC) substrates. Remarkably, Py/PC devices exhibit an exceptionally large inductance variation exceeding 1 μH at room temperature, and intriguingly, a sign reversal of inductance occurs around the zero magnetic field. The dependencies of the EML effect on frequency, step magnetic field changes, and film width can be explained from the theory based on the spin motive force driven by transient domain wall motion. This study opens up exciting avenues for advancing our understanding of emergent inductance in fundamental physics and paves the way for practical applications in flexible magnetic devices.

Spin textures, such as magnetic domain walls and skyrmions, have the potential to revolutionize electronic devices by encoding information bits. Although recent advancements in ferromagnetic films have led to promising device prototypes, their widespread implementation has been hindered by material-related drawbacks. Antiferromagnetic spin textures, however, offer a solution to many of these limitations, paving the way for faster, smaller, more energy-efficient, and more robust electronics. The functionality of synthetic antiferromagnets, comprised of two or more magnetic layers separated by spacers, may be easily manipulated by making use of different materials as well as interface engineering. In this Perspective article, we examine the challenges and opportunities presented by spin textures in synthetic antiferromagnets and propose possible directions and prospects for future research in this burgeoning field.

Two-dimensional (2D) multiferroic materials with distinctive properties, such as half-metallicity, high Curie temperature (TC), and magnetoelastic coupling, hold potential applications in novel nanoscale spintronic devices, but they are rare. Using density functional theory (DFT) calculations and evolutionary algorithms, we identify new types of 2D NiOX (X = F, Cl and Br) monolayers that are stable in energy, dynamics, thermodynamics, and mechanics. Among them, NiOF is an indirect-gap antiferromagnetic (AFM) semiconductor, while NiOCl and NiOBr are half-metallic materials with ferromagnetic (FM) ordering with a TC of 671 and 692 K and in-plane magnetic anisotropy energies (MAEs) of 541 and 609 μeV per Ni along the x-axis and y-axis, respectively. Notably, ferroelasticity is another important feature of NiOCl and NiOBr monolayers with energy barriers of 234.0 and 151.5 meV per atom, respectively. Moreover, the in-plane magnetic easy axis is strongly coupled to the lattice direction. The coexistence of high ferromagnetism, ferroelasticity, half-metallicity, and magnetoelastic coupling renders NiOCl and NiOBr monolayers great potential for future nanodevices.