Dimensionality Engineering of Magnetic Anisotropy from the Anomalous Hall Effect in Synthetic SrRuO3 Crystals.

Magnetic anisotropy in atomically thin correlated heterostructures is essential for exploring quantum magnetic phases for next-generation spintronics. Whereas previous studies have mostly focused on van der Waals systems, here we investigate the impact of dimensionality of epitaxially grown correlated oxides down to the monolayer limit on structural, magnetic, and orbital anisotropies. By designing oxide superlattices with a correlated ferromagnetic SrRuO3 and nonmagnetic SrTiO3 layers, we observed modulated ferromagnetic behavior with the change of the SrRuO3 thickness. Especially, for three-unit-cell-thick layers, we observe a significant 1500% improvement of the coercive field in the anomalous Hall effect, which cannot be solely attributed to the dimensional crossover in ferromagnetism. The atomic-scale heterostructures further reveal the systematic modulation of anisotropy for the lattice structure and orbital hybridization, explaining the enhanced magnetic anisotropy. Our findings provide valuable insights into engineering the anisotropic hybridization of synthetic magnetic crystals, offering a tunable spin order for various applications.

Symmetry Engineering of Epitaxial Hf0.5Zr0.5O2 Ultrathin Films.

Robust ferroelectricity in HfO2-based ultrathin films has the potential to revolutionize nonvolatile memory applications in nanoscale electronic devices because of their compatibility with the existing Si technology. However, to fully exploit the potential of ferroelectric HfO2-based thin films, it is crucial to develop strategies for the controlled stabilization of various HfO2-based polymorphs in nanoscale heterostructures. This study demonstrates how substrate-orientation-induced anisotropic strain can engineer the crystal symmetry, structural domain morphology, and growth orientation of ultrathin Hf0.5Zr0.5O2 (HZO) films. Epitaxial ultrathin HZO films were grown on the heterostructures of (001)- and (110)-oriented La2/3Sr1/3MnO3/SrTiO3 (LSMO/STO) substrate. Various structural analyses revealed that the (110)-oriented substrate promotes a higher degree of structural order (crystallinity) with improved stability of the (111)-oriented orthorhombic phase (Pca21) of HZO. Conversely, the (001)-oriented substrate not only induces a distorted orthorhombic structure but also facilitates the partial stabilization of nonpolar phases. Electrical measurements revealed robust ferroelectric properties in epitaxial thin films without any wake-up effect, where the well-ordered crystal symmetry stabilized by STO(110) facilitated better ferroelectric characteristics. This study suggests that tuning the epitaxial growth of ferroelectric HZO through substrate orientation can improve the stability of the metastable ferroelectric orthorhombic phase and thereby offer a better understanding of device applications.

Te-rP-C Anodes Prepared Using a Scalable Milling Process for High-Performance Lithium-Ion Batteries.

Red phosphorus (rP) is one of the most promising anode materials for lithium-ion batteries, owing to its high theoretical capacity. However, its low electronic conductivity and large volume expansion during cycling limit its practical applications, as it exhibits low electrochemical activity and unstable cyclability. To address these problems, tellurium (Te)-rP-C composites, which have active materials (Te, rP) that are uniformly distributed within the carbon matrix, were fabricated through a simple high-energy ball milling method. Among the three electrodes, the Te-rP (1:2)-C electrode with a 5% FEC additive delivers a high initial CE of 80% and a high reversible capacity of 734 mAh g-1 after 300 cycles at a current density of 100 mA g-1. Additionally, it exhibits a high-rate capacity of 580 mAh g-1 at a high current density of 10,000 mA g-1. Moreover, a comparison of the electrolytes with and without the 5% FEC additive demonstrated improved cycling stability when the FEC additive was used. Ex situ XRD analysis demonstrated the lithiation/delithiation mechanism of Te-rP (1:2)-C after cycling based on the cyclic voltammetry results. Based on the electrochemical impedance spectroscopy analysis results, a Te-rP-C composite with its notable electrochemical performance as an anode can sufficiently contribute to the battery anode industry.

Exotic Magnetic Anisotropy Near Digitized Dimensional Mott Boundary.

The magnetic anisotropy of low-dimensional Mott systems exhibits unexpected magnetotransport behavior useful for spin-based quantum electronics. Yet, the anisotropy of natural materials is inherently determined by the crystal structure, highly limiting its engineering. The magnetic anisotropy modulation near a digitized dimensional Mott boundary in artificial superlattices composed of a correlated magnetic monolayer SrRuO3 and nonmagnetic SrTiO3 , is demonstrated. The magnetic anisotropy is initially engineered by modulating the interlayer coupling strength between the magnetic monolayers. Interestingly, when the interlayer coupling strength is maximized, a nearly degenerate state is realized, in which the anisotropic magnetotransport is strongly influenced by both the thermal and magnetic energy scales. The results offer a new digitized control for magnetic anisotropy in low-dimensional Mott systems, inspiring promising integration of Mottronics and spintronics.

Controlled Electronic and Magnetic Landscape in Self-Assembled Complex Oxide Heterostructures.

Complex oxide heterointerfaces contain a rich playground of novel physical properties and functionalities, which give rise to emerging technologies. Among designing and controlling the functional properties of complex oxide film heterostructures, vertically aligned nanostructure (VAN) films using a self-assembling bottom-up deposition method presents great promise in terms of structural flexibility and property tunability. Here, the bottom-up self-assembly is extended to a new approach using a mixture containing a 2Dlayer-by-layer film growth, followed by a 3D VAN film growth. In this work, the two-phase nanocomposite thin films are based on LaAlO3 :LaBO3 , grown on a lattice-mismatched SrTiO3001 (001) single crystal. The 2D-to-3D transient structural assembly is primarily controlled by the composition ratio, leading to the coexistence of multiple interfacial properties, 2D electron gas, and magnetic anisotropy. This approach provides multidimensional film heterostructures which enrich the emergent phenomena for multifunctional applications.

Giant Enhancement of Electron-Phonon Coupling in Dimensionality-Controlled SrRuO3 Heterostructures.

Electrons in crystals interact closely with quantized lattice degree of freedom, determining fundamental electrodynamic behaviors and versatile correlated functionalities. However, the strength of the electron-phonon interaction is so far determined as an intrinsic value of a given material, restricting the development of potential electronic and phononic applications employing the tunable coupling strength. Here, it is demonstrated that the electron-phonon coupling in SrRuO3 can be largely controlled by multiple intuitive tuning knobs available in synthetic crystals. The coupling strength of quasi-2D SrRuO3 is enhanced by ≈300-fold compared with that of bulk SrRuO3 . This enormous enhancement is attributed to the non-local nature of the electron-phonon coupling within the well-defined synthetic atomic network, which becomes dominant in the limit of the 2D electronic state. These results provide valuable opportunities for engineering the electron-phonon coupling, leading to a deeper understanding of the strongly coupled charge and lattice dynamics in quantum materials.

Sagnac Effect Compensations and Locked States in a Ring Laser Gyroscope.

Frequency lock-in-induced deadband phenomena are major problems of ring laser gyroscopes (RLGs), which deteriorate linear responses to changes in the applied rotation rate. In this work, the frequency lock-in phenomenon occurring in the RLG was successfully investigated by compensating for the Sagnac effect through frequency analysis using a newly defined error function. Integrative and generalized viewpoints from the analyzed results provide new possibilities for relevant performance improvements of optical gyroscopes, as well as a deeper understanding of locked states in principle aspects.

Atomic-Scale Modulation of Synthetic Magnetic Order in Oxide Superlattices.

Atomic-scale precision control of magnetic interactions facilitates a synthetic spin order useful for spintronics, including advanced memory and quantum logic devices. Conventional modulation of synthetic spin order has been limited to metallic heterostructures that exploit Ruderman-Kittel-Kasuya-Yosida interaction through a nonmagnetic metallic spacer; however, they face issues arising from Joule heating and/or electric breakdown. The practical realization and observation of a synthetic spin order across a nonmagnetic insulating spacer will lead to the development of spin-related devices with a completely different concept. Herein, the atomic-scale modulation of the synthetic spiral spin order in oxide superlattices composed of ferromagnetic metal and nonmagnetic insulator layers is reported. The atomically controlled superlattice exhibits an oscillatory magnetic behavior, representing the existence of a spiral spin structure. Depth-sensitive polarized neutron reflectometry evidences modulated spiral spin structures as a function of the nonmagnetic insulator layer thickness. Atomic-scale customization of the spin state can move the field one step further to actual spintronic applications.

Homonymous hemianopia due to cerebral venous thrombosis: A case report.

RATIONALE: Diagnosing cerebral venous thrombosis (CVT) can be difficult because of nonspecific symptoms, such as headache and homonymous hemianopia (HH). Herein, we present a case of delayed CVT diagnosis due to nonspecific neurological symptoms and nonprominent lesions in a patient with HH. PATIENT CONCERN: A 65-year-old woman presented with a sudden onset headache accompanied by right HH that lasted for 1 day. Brain computed tomography and magnetic resonance imaging were initially performed due to suspicion of ischemic lesions or hemorrhage in the left postchiasmal visual pathway; however, no remarkable acute brain lesions were detected. Ophthalmological examinations revealed no notable findings, except for a definite field defect in the Humphrey visual field test. The headaches then waxed and waned but recurred 3 days after the initial symptom.A repeat brain magnetic resonance imaging was performed, which revealed left sectoral gyral swelling and vascular enhancement in the occipital lobe. To further evaluate venous drainage, additional 3-dimensional cerebral computed tomography angiography and 4-vessel angiography were conducted, revealing a partial filling defect in the left transverse sinus and superior venous drainage impairment. These findings suggested the presence of venous thrombosis in the left transverse sinus. DIAGNOSIS: The patient was diagnosed with thrombosis of the left transverse sinus, which subsequently caused the right HH. INTERVENTION: Anticoagulation therapy with parenteral heparin was started as soon as the diagnosis of CVT was confirmed. Eventually, the patient was solely managed with oral warfarin administration. OUTCOMES: Following 3 days of treatment, her headache resolved, and a subsequent visual field testing conducted 2 weeks later revealed a definite improvement in the field defect. LESSONS: Despite its favorable prognosis, CVT can be challenging to diagnose. CVT should be considered as a differential diagnosis when diagnosing patients who present with headaches accompanied by HH without prominent brain lesions.

Study on superconducting properties of CeIrIn5thin films grown via pulsed laser deposition.

We report the growth of CeIrIn5thin films with different crystal orientations on a MgF2(001) substrate using pulsed laser deposition technique. X-ray diffraction analysis showed that the thin films were either mainlya-axis-oriented (TF1) or a combination ofa- andc-axis-oriented (TF2). The characteristic features of heavy-fermion superconductors, i.e. Kondo coherence and superconductivity, were clearly observed, where the superconducting transition temperature (Tc) and Kondo coherence temperature (Tcoh) are 0.58 K and 41 K for TF1 and 0.52 K and 37 K for TF2, respectively. The temperature dependencies of the upper critical field (Hc2) of both thin films and the CeIrIn5single crystal revealed a scaling behavior, indicating that the nature of unconventional superconductivity has not been changed in the thin film. The successful synthesis of CeIrIn5thin films is expected to open a new avenue for novel quantum phases that may have been difficult to explore in the bulk crystalline samples.

High critical current density and high-tolerance superconductivity in high-entropy alloy thin films.

High-entropy alloy (HEA) superconductors-a new class of functional materials-can be utilized stably under extreme conditions, such as in space environments, owing to their high mechanical hardness and excellent irradiation tolerance. However, the feasibility of practical applications of HEA superconductors has not yet been demonstrated because the critical current density (Jc) for HEA superconductors has not yet been adequately characterized. Here, we report the fabrication of high-quality superconducting (SC) thin films of Ta-Nb-Hf-Zr-Ti HEAs via a pulsed laser deposition. The thin films exhibit a large Jc of >1 MA cm-2 at 4.2 K and are therefore favorable for SC devices as well as large-scale applications. In addition, they show extremely robust superconductivity to irradiation-induced disorder controlled by the dose of Kr-ion irradiation. The superconductivity of the HEA films is more than 1000 times more resistant to displacement damage than that of other promising superconductors with technological applications, such as MgB2, Nb3Sn, Fe-based superconductors, and high-Tc cuprate superconductors. These results demonstrate that HEA superconductors have considerable potential for use under extreme conditions, such as in aerospace applications, nuclear fusion reactors, and high-field SC magnets.

A Multimodal Approach to Huge Fibrous Dysplasia With Ocular Symptoms Using a Navigation System and Endoscope.

BACKGROUND: Fibrous dysplasia (FD) is a rare sporadic benign disease, which involves from single to several bones with unilateral distribution. Recently, image-based surgical navigation systems have played a significant role in surgical process on neurological and orthopedic operations. However, because an intraoral approach can visualize the field for maxillary surgery, there are few cases using endoscopes for excision of FD. Even though, a huge mass involving posterior side of maxillary sinus can be assisted with an endoscope to protect essential structures. To the best of our knowledge, this is the first report of plastic and reconstructive surgeons to perform the operation of a huge FD with both an endoscope and a navigation system. METHODS: Preoperative computed tomography scan and magnetic resonance imaging was performed for precise diagnosis and setting the navigation system (Medtronic Navigation, Louisville, CO). The main problem of the patient was exophthalmos and decreased visual acuity, the authors decided to remove the mass involving the intraorbital portion and sphenoidal portion. Moreover, the mass was extending to intracranium, cooperation with the department of neurosurgery and otolaryngology was planned. The tumor reached by the endoscope was resected as much as possible. During the excision of the sphenoidal portion by the head and neck surgeon of the department of otolaryngology, cerebrospinal fluid leakage was observed and repaired by the neurosurgeon. RESULTS: The exophthalmos measured by Hertel exophthalmometry was reduced only 1 mm, however, gross morphology of the patient was totally changed after the operation. Visual acuity of the right eye was improved from 0.3 to 0.9. The patient was followed up about 6 months and had a seizure event at 2 weeks after the surgery. Afterwards, the symptom has been well controlled by the medication. CONCLUSIONS: This multimodal approach offers a safe, rapid surgical aid in treating huge lesions involving orbital and intracranial area.

Unconventional interlayer exchange coupling via chiral phonons in synthetic magnetic oxide heterostructures.

Chiral symmetry breaking of phonons plays an essential role in emergent quantum phenomena owing to its strong coupling to spin degree of freedom. However, direct experimental evidence of the chiral phonon-spin coupling is lacking. In this study, we report a chiral phonon-mediated interlayer exchange interaction in atomically controlled ferromagnetic metal (SrRuO3)-nonmagnetic insulator (SrTiO3) heterostructures. Owing to the unconventional interlayer exchange interaction, we have observed rotation of spins as a function of nonmagnetic insulating spacer thickness, resulting in a spin spiral state. The chiral phonon-spin coupling is further confirmed by phonon Zeeman effect. The existence of the chiral phonons and their interplay with spins along with our atomic-scale heterostructure approach unveil the crucial roles of chiral phonons in magnetic materials.

Atomistic Engineering of Phonons in Functional Oxide Heterostructures.

Engineering of phonons, that is, collective lattice vibrations in crystals, is essential for manipulating physical properties of materials such as thermal transport, electron-phonon interaction, confinement of lattice vibration, and optical polarization. Most approaches to phonon-engineering have been largely limited to the high-quality heterostructures of III-V compound semiconductors. Yet, artificial engineering of phonons in a variety of materials with functional properties, such as complex oxides, will yield unprecedented applications of coherent tunable phonons in future quantum acoustic devices. In this study, artificial engineering of phonons in the atomic-scale SrRuO3 /SrTiO3 superlattices is demonstrated, wherein tunable phonon modes are observed via confocal Raman spectroscopy. In particular, the coherent superlattices led to the backfolding of acoustic phonon dispersion, resulting in zone-folded acoustic phonons in the THz frequency domain. The frequencies can be largely tuned from 1 to 2 THz via atomic-scale precision thickness control. In addition, a polar optical phonon originating from the local inversion symmetry breaking in the artificial oxide superlattices is observed, exhibiting emergent functionality. The approach of atomic-scale heterostructuring of complex oxides will vastly expand material systems for quantum acoustic devices, especially with the viability of functionality integration.

An Updated Meta-Analysis of Remote Blood Pressure Monitoring in Urban-Dwelling Patients with Hypertension.

Following the coronavirus disease-2019 pandemic, this study aimed to evaluate the overall effects of remote blood pressure monitoring (RBPM) for urban-dwelling patients with hypertension and high accessibility to healthcare and provide updated quantitative summary data. Of 2721 database-searched articles from RBPM's inception to November 2020, 32 high-quality studies (48 comparisons) were selected as primary data for synthesis. A meta-analysis was undertaken using a random effects model. Primary outcomes were changes in office systolic blood pressure (SBP) and diastolic blood pressure (DBP) following RBPM. The secondary outcome was the BP control rate. Compared with a usual care group, there was a decrease in SBP and DBP in the RBPM group (standardized mean difference 0.507 (95% confidence interval [CI] 0.339-0.675, p < 0.001; weighted mean difference [WMD] 4.464 mmHg, p < 0.001) and 0.315 (CI 0.209-0.422, p < 0.001; WMD 2.075 mmHg, p < 0.001), respectively). The RBPM group had a higher BP control rate based on a relative ratio (RR) of 1.226 (1.107-1.358, p < 0.001). RBPM effects increased with increases in city size and frequent monitoring, with decreases in intervention duration, and in cities without medically underserved areas. RBPM is effective in reducing BP and in achieving target BP levels for urban-dwelling patients with hypertension.

Contribution of the Sub-Surface to Electrocatalytic Activity in Atomically Precise La0.7 Sr0.3 MnO3 Heterostructures.

Electrocatalytic reactions are known to take place at the catalyst/electrolyte interface. Whereas recent studies of size-dependent activity in nanoparticles and thickness-dependent activity of thin films imply that the sub-surface layers of a catalyst can contribute to the catalytic activity as well, most of these studies consider actual modification of the surfaces. In this study, the role of catalytically active sub-surface layers was investigated by employing atomic-scale thickness control of the La0.7 Sr0.3 MnO3 (LSMO) films and heterostructures, without altering the catalyst/electrolyte interface. The activity toward the oxygen evolution reaction (OER) shows a non-monotonic thickness dependence in the LSMO films and a continuous screening effect in LSMO/SrRuO3 heterostructures. The observation leads to the definition of an "electrochemically-relevant depth" on the order of 10 unit cells. This study on the electrocatalytic activity of epitaxial heterostructures provides new insight in designing efficient electrocatalytic nanomaterials and core-shell architectures.

Correlated oxide Dirac semimetal in the extreme quantum limit.

Quantum materials (QMs) with strong correlation and nontrivial topology are indispensable to next-generation information and computing technologies. Exploitation of topological band structure is an ideal starting point to realize correlated topological QMs. Here, we report that strain-induced symmetry modification in correlated oxide SrNbO3 thin films creates an emerging topological band structure. Dirac electrons in strained SrNbO3 films reveal ultrahigh mobility (µmax ≈ 100,000 cm2/Vs), exceptionally small effective mass (m* ~ 0.04me), and nonzero Berry phase. Strained SrNbO3 films reach the extreme quantum limit, exhibiting a sign of fractional occupation of Landau levels and giant mass enhancement. Our results suggest that symmetry-modified SrNbO3 is a rare example of correlated oxide Dirac semimetals, in which strong correlation of Dirac electrons leads to the realization of a novel correlated topological QM.

Nurse-Coordinated Blood Pressure Telemonitoring for Urban Hypertensive Patients: A Systematic Review and Meta-Analysis.

Coronavirus disease 2019 (COVID-19) has put hypertensive patients in densely populated cities at increased risk. Nurse-coordinated home blood pressure telemonitoring (NC-HBPT) may help address this. We screened studies published in English on three databases, from their inception to 30 November 2020. The effects of NC-HBPT were compared with in-person treatment. Outcomes included changes in blood pressure (BP) following the intervention and rate of BP target achievements before and during COVID-19. Of the 1916 articles identified, 27 comparisons were included in this review. In the intervention group, reductions of 5.731 mmHg (95% confidence interval: 4.120-7.341; p < 0.001) in systolic blood pressure (SBP) and 2.342 mmHg (1.482-3.202; p < 0.001) in diastolic blood pressure (DBP) were identified. The rate of target BP achievement was significant in the intervention group (risk ratio, RR = 1.261, 1.154-1.378; p < 0.001). The effects of intervention over time showed an SBP reduction of 3.000 mmHg (-5.999-11.999) before 2000 and 8.755 mmHg (5.177-12.334) in 2020. DBP reduced by 2.000 mmHg (-2.724-6.724) before 2000 and by 3.529 mmHg (1.221-5.838) in 2020. Analysis of the target BP ratio before 2010 (RR = 1.101, 1.013-1.198) and in 2020 (RR = 1.906, 1.462-2.487) suggested improved BP control during the pandemic. NC-HBPT more significantly improves office blood pressure than UC among urban hypertensive patients.

Strain-Induced Atomic-Scale Building Blocks for Ferromagnetism in Epitaxial LaCoO3.

The origin of strain-induced ferromagnetism, which is robust regardless of the type and degree of strain in LaCoO3 (LCO) thin films, is enigmatic despite intensive research efforts over the past decade. Here, by combining scanning transmission electron microscopy with ab initio density functional theory plus U calculations, we report that the ferromagnetism does not emerge directly from the strain itself but rather from the creation of compressed structural units within ferroelastically formed twin-wall domains. The compressed structural units are magnetically active with the rocksalt-type high-spin/low-spin order. Our study highlights that the ferroelastic nature of ferromagnetic structural units is important for understanding the intriguing ferromagnetic properties in LCO thin films.

Color of Copper/Copper Oxide.

Stochastic inhomogeneous oxidation is an inherent characteristic of copper (Cu), often hindering color tuning and bandgap engineering of oxides. Coherent control of the interface between metal and metal oxide remains unresolved. Coherent propagation of an oxidation front in single-crystal Cu thin film is demonstrated to achieve a full-color spectrum for Cu by precisely controlling its oxide-layer thickness. Grain-boundary-free and atomically flat films prepared by atomic-sputtering epitaxy allow tailoring of the oxide layer with an abrupt interface via heat treatment with a suppressed temperature gradient. Color tuning of nearly full-color red/green/blue indices is realized by precise control of the oxide-layer thickness; the samples cover ≈50.4% of the standard red/green/blue color space. The color of copper/copper oxide is realized by the reconstruction of the quantitative yield color from the oxide "pigment" (complex dielectric functions of Cu2 O) and light-layer interference (reflectance spectra obtained from the Fresnel equations) to produce structural color. Furthermore, laser-oxide lithography is demonstrated with micrometer-scale linewidth and depth through local phase transformation to oxides embedded in the metal, providing spacing necessary for semiconducting transport and optoelectronics functionality.