Spatial Filtering of Interlayer Exciton Ground State in WSe2/MoS2 Heterobilayer.

Long-life interlayer excitons (IXs) in transition metal dichalcogenide (TMD) heterostructure are promising for realizing excitonic condensates at high temperatures. Critical to this objective is to separate the IX ground state (the lowest energy of IX state) emission from other states' emissions. Filtering the IX ground state is also essential in uncovering the dynamics of correlated excitonic states, such as the excitonic Mott insulator. Here, we show that the IX ground state in the WSe2/MoS2 heterobilayer can be separated from other states by its spatial profile. The emissions from different moiré IX modes are identified by their different energies and spatial distributions, which fits well with the rate-diffusion model for cascading emission. Our results show spatial filtering of the ground state mode and enrich the toolbox to realize correlated states at elevated temperatures.

Compound Shenma Jingfu granule alleviates cerebral ischemia via HIF-1α-mediated promotion of angiogenesis.

BACKGROUND: Shenma Jingfu Granule, a traditional Chinese medicine formula, has been used clinically for the treatment of cerebral circulation insufficiency. However, the mechanism involved in alleviating cerebral ischemia has not yet been fully elucidated. METHODS: An integrated approach involving network pharmacology and transcriptomics was utilized to clarify the potential mechanisms of SMJF Granule. Molecular docking and surface plasmon resonance (SPR) were employed to identify potential targets and ingredients of SMJF Granule. The anti-CI effect of SMJF Granule was determined on the middle cerebral artery occlusion (MCAO) model by using hematoxylin-eosin (H&E) and Nissl's staining, as well as triphenyl tetrazolium chloride (TTC) staining, and the potential targets involved in the mechanisms were validated by RT-qPCR and western blotting. RESULTS: Integrated analysis revealed the mechanism of SMJF Granule intervening in CI injury might be related to the HIF-1 signaling pathway and angiogenesis. Molecular docking and SPR assays demonstrated robust binding interactions between key compounds like salvianolic acid A and naringenin with the core target HIF-1α protein. The experiment confirmed that SMJF Granule lowered neurological scores, diminished infarct volume, and alleviated histopathological changes in vivo. The possible mechanism of SMJF Granule was due to regulating HIF-1 pathway, which contributed to up-regulating expression of VEGF and vWF in the penumbral region, showing a significant promotion of angiogenesis. CONCLUSION: SMJF Granule promoted angiogenesis through HIF-1α pathway, thereby alleviating cerebral ischemia injury. In addition, our findings provide some evidence that SMJF Granule is a candidate compound for further investigation in treating CI in the clinical.

Observation of plaid-like spin splitting in a noncoplanar antiferromagnet.

Spatial, momentum and energy separation of electronic spins in condensed-matter systems guides the development of new devices in which spin-polarized current is generated and manipulated1-3. Recent attention on a set of previously overlooked symmetry operations in magnetic materials4 leads to the emergence of a new type of spin splitting, enabling giant and momentum-dependent spin polarization of energy bands on selected antiferromagnets5-10. Despite the ever-growing theoretical predictions, the direct spectroscopic proof of such spin splitting is still lacking. Here we provide solid spectroscopic and computational evidence for the existence of such materials. In the noncoplanar antiferromagnet manganese ditelluride (MnTe2), the in-plane components of spin are found to be antisymmetric about the high-symmetry planes of the Brillouin zone, comprising a plaid-like spin texture in the antiferromagnetic (AFM) ground state. Such an unconventional spin pattern, further found to diminish at the high-temperature paramagnetic state, originates from the intrinsic AFM order instead of spin-orbit coupling (SOC). Our finding demonstrates a new type of quadratic spin texture induced by time-reversal breaking, placing AFM spintronics on a firm basis and paving the way for studying exotic quantum phenomena in related materials.

Deciphering Density Fluctuations in the Hydration Water of Brownian Nanoparticles via Upconversion Thermometry.

We investigate the intricate relationship among temperature, pH, and Brownian velocity in a range of differently sized upconversion nanoparticles (UCNPs) dispersed in water. These UCNPs, acting as nanorulers, offer insights into assessing the relative proportion of high-density and low-density liquid in the surrounding hydration water. The study reveals a size-dependent reduction in the onset temperature of liquid-water fluctuations, indicating an augmented presence of high-density liquid domains at the nanoparticle surfaces. The observed upper-temperature threshold is consistent with a hypothetical phase diagram of water, validating the two-state model. Moreover, an increase in pH disrupts the organization of water molecules, similar to external pressure effects, allowing simulation of the effects of temperature and pressure on hydrogen bonding networks. The findings underscore the significance of the surface of suspended nanoparticles for understanding high- to low-density liquid fluctuations and water behavior at charged interfaces.

Interlayer donor-acceptor pair excitons in MoSe2/WSe2 moiré heterobilayer.

Localized interlayer excitons (LIXs) in two-dimensional moiré superlattices exhibit sharp and dense emission peaks, making them promising as highly tunable single-photon sources. However, the fundamental nature of these LIXs is still elusive. Here, we show the donor-acceptor pair (DAP) mechanism as one of the origins of these excitonic peaks. Numerical simulation results of the DAP model agree with the experimental photoluminescence spectra of LIX in the moiré MoSe2/WSe2 heterobilayer. In particular, we find that the emission energy-lifetime correlation and the nonmonotonic power dependence of the lifetime agree well with the DAP IX model. Our results provide insight into the physical mechanism of LIX formation in moiré heterostructures and pave new directions for engineering interlayer exciton properties in moiré superlattices.

Progressively Oriented Attachment-Enabled Ultralong Single-Crystalline Upconversion Nanowires for Multidirectional Strain Sensing.

Fabricating one-dimensional (1D) single-crystalline nanostructures with the necessary characteristics for interconnects and functional units in nanodevices poses a major challenge. Traditional solution-based synthesis methods, driven by oriented attachment mechanisms, have limited the growth of either ultrathin crystalline nanowires or short rod-like nanocrystals due to stringent orientation requirements. The construction of single-crystalline ultralong nanowires with both an elongated length and moderate thickness has remained elusive. Here we introduce a growth mechanism based on progressively oriented attachment that enables the attachment of larger crystals while preserving the alignment of the crystal lattice. Using this mechanism, we achieve 1D single-crystalline lanthanide-doped nanowires (K2YF5:Yb/Er) with lengths up to 9 µm and a moderate thickness of approximately 20 nm. These nanowires can be integrated into a flexible film that exhibits stretching-dependent upconverted luminescence behavior. The mechanical toughness and elongated morphology of the nanowires facilitate the development of a wearable device dedicated to multidirectional strain sensing with high responsivity and excellent stability, withstanding repeated stretching and releasing for up to 1000 cycles.

Spin Defects in hBN assisted by Metallic Nanotrenches for Quantum Sensing.

The omnipresence of hexagonal boron nitride (hBN) in devices embedding two-dimensional materials has prompted it as the most sought after platform to implement quantum sensing due to its testing while operating capability. The negatively charged boron vacancy (VB-) in hBN plays a prominent role, as it can be easily generated while its spin population can be initialized and read out by optical means at room-temperature. But the lower quantum yield hinders its widespread use as an integrated quantum sensor. Here, we demonstrate an emission enhancement amounting to 400 by nanotrench arrays compatible with coplanar waveguide (CPW) electrodes employed for spin-state detection. By monitoring the reflectance spectrum of the resonators as additional layers of hBN are transferred, we have optimized the overall hBN/nanotrench optical response, maximizing thereby the luminescence enhancement. Based on these finely tuned heterostructures, we achieved an enhanced DC magnetic field sensitivity as high as 6 × 10-5 T/Hz1/2.

Magnetically Tunable Spontaneous Superradiance from Mesoscopic Perovskite Emitter Clusters.

Perovskite emitters are promising materials as next-generation optical sources due to their low fabrication cost and high quantum yield. In particular, the superradiant emission from a few coherently coupled perovskite emitters can be used to produce a bright entangled photon source. Here, we report the observation of superradiance from mesoscopic (<55) CsPbBr3 perovskite emitters, which have a much smaller ensemble size than the previously reported results (>106 emitters). The superradiance is spontaneously generated by off-resonance excitation and detected by time-resolved photoluminescence and second-order photon correlation measurements. We observed a remarkable magnetic tunability of the superradiant photon bunching, indicating a magnetic field-induced decoherence process. The experimental results can be well explained using a theoretical framework based on the microscopic master equation. Our findings shed light on the superradiance mechanism in perovskite emitters and enable low-cost quantum light sources based on perovskite.

Anomalous intense coherent secondary photoemission from a perovskite oxide.

Photocathodes-materials that convert photons into electrons through a phenomenon known as the photoelectric effect-are important for many modern technologies that rely on light detection or electron-beam generation1-3. However, current photocathodes are based on conventional metals and semiconductors that were mostly discovered six decades ago with sound theoretical underpinnings4,5. Progress in this field has been limited to refinements in photocathode performance based on sophisticated materials engineering1,6. Here we report unusual photoemission properties of the reconstructed surface of single crystals of the perovskite oxide SrTiO3(100), which were prepared by simple vacuum annealing. These properties are different from the existing theoretical descriptions4,7-10. In contrast to other photocathodes with a positive electron affinity, our SrTiO3 surface produces, at room temperature, discrete secondary photoemission spectra, which are characteristic of efficient photocathode materials with a negative electron affinity11,12. At low temperatures, the photoemission peak intensity is enhanced substantially and the electron beam obtained from non-threshold excitations shows longitudinal and transverse coherence that differs from previous results by at least an order of magnitude6,13,14. The observed emergence of coherence in secondary photoemission points to the development of a previously undescribed underlying process in addition to those of the current theoretical photoemission framework. SrTiO3 is an example of a fundamentally new class of photocathode quantum materials that could be used for applications that require intense coherent electron beams, without the need for monochromatic excitations.

Interplay of Purcell effect and extraction efficiency in CsPbBr3 quantum dots coupled to Mie resonators.

Inorganic halide perovskite quantum dots have risen in recent years as efficient active materials in numerous optoelectronic applications ranging from solar cells to light-emitting diodes and lasers, and have lately been tested as quantum emitters. Perovskite quantum dots are often coupled to photonic structures either to enhance their emission properties, by accelerating their emission rate thanks to the Purcell effect, or to increase light extraction. From a theoretical point of view, the first effect is often considered at the single-dipole level while the latter is often treated at the mesoscopic level, except possibly for quantum emitters. In this work we employ a layer of perovskite quantum dots coupled to dielectric Mie resonators to exploit both effects simultaneously and achieve an 18-fold increase in luminescence. Our numerical simulations, combined with spatially- and time-resolved photoluminescence measurements, reveal how the macroscopic response of the perovskite-on-Mie resonator structure results from the interplay of the two effects averaged over the whole spatial distribution of emitters. Our work provides thus guiding principles for maximizing the output intensity of quantum emitters embedded into photonic resonators as well as classical emitters integrated in perovskite-based optoelectronic devices.

Physical Fitness Recovery of Athletes Based on High-Intensity Sports Intermittent Training.

Baseball itself is a new sport. In the process of training, teachers often use traditional training methods, which leads to unsatisfactory training results. High-intensity intermittent and intensive interval training can better improve the efficiency of athletes' oxidation and energy supply and ultimately play a positive role in improving athletes' performance. This paper takes the influence of high-intensity and intensive interval training on the special endurance of baseball players as the research object. A series of functional training programs are developed through adaptive training, testing, coordination training, and recovery training. Through the use of experimental means to understand the influence of high-intensity interval training and intensive interval training on the physical fitness of baseball players, the paper is aimed at providing ways and means to improve the physical fitness level of baseball players in the future. Based on the experimental test data, functional training is different from traditional training methods to make up for the lack of training research. It is to improve the competitive ability of our baseball players and promote the development of our baseball. It plays an active role in improving the specific endurance, speed, and intermittent endurance of baseball players.

The Balance Reaction Ability of Teenagers Based on the Evaluation Model of Unbalanced Sports Quotient.

Dynamic balance is particularly important for the maintenance, transformation, and restabilization of various postures of the human body. Combined with the characteristics of unbalanced sports events, although there is no physical contact in sports events, it has intense antagonism due to the constant change of body movement. Athletes need to have the ability of fast movement and continuous high-intensity multibeat confrontation. They need to adjust their body posture any time according to the situation, constantly move their body from one side to the other side in fast movement, and constantly change between being imbalanced and being stable to keep the center of gravity stable and adjust their body posture. Combining with the characteristics of unbalanced sports, this paper is aimed at the problem that young athletes have poor dynamic balance ability and cannot maintain the stability of their body's center of gravity in the process of fast multidirectional movement and braking. The supporting leg needs ankle dorsiflexion, knee flexion, and hip flexion during SEBT testing. Therefore, the lower limb needs sufficient range of motion, strength, proprioception, and neuromuscular control ability to achieve the optimal test results. A randomized controlled experiment was used to test whether there were significant differences in the test indicators between the experimental group and the control group before and after the experiment by using a paired test. The test indicators between the experimental group and the control group before and after the intervention were tested by independent sample test to explore the influence of core balance training on the dynamic balance ability of teenagers in unbalanced sports. Through analysis, it is proved that strengthening balance exercise can significantly improve the functional movements and physical fitness of adolescents, which is of great significance to the development of basic flexibility and stability of joints and the strengthening of weak chain muscles.

Static Model of Athlete's Upper Limb Posture Rehabilitation Training Indexes.

With the gradual expansion of the development of sports, the level of sports has been rapidly improved. Athletes have to carry out high-intensity and systemic technical movements in training and competition. Some sports have the greatest burden on the shoulder joint. From the observation and investigation of the injured parts of athletes, it is found that the shoulder joint is the most common sports injury, which is the most typical sports injury. Based on the problem of insufficient strength and endurance reserve after rehabilitation of shoulder external rotator injury, it will cause muscle tension and poor extensibility. To prove the improvement effect of functional training and posture index calibration on the poor posture of the shoulder, considering the measurement of global passive torque, this paper uses a limited set of joint angles and corresponding passive torque data in the upper arm lifting trajectory to train the neural network and uses the trained network to predict the passive torque in other upper arm trajectories. The kinematics model of the shoulder joint is established, and the human-computer interaction experiment is designed on the platform of the gesture index manipulator. The passive and active torque components of the shoulder joint in the human-computer interaction process are calculated by measuring the man-machine interaction force of the subjects in the motion state, which is used as the basis for evaluating the active motion intention of the subjects. Surface electromyography (SEMG) was used to calibrate and verify the attitude index of shoulder active torque. The method proposed in this paper is helpful to achieve more efficient on-demand assisted rehabilitation training exercises, which is of great significance to improve the level of rehabilitation training.

Experimental Analysis of the Effect of Rehabilitation Intervention on Tennis Players by Joint Injury Treatment.

In the process of competition and training, tennis players often carry out explosive force and extreme centripetal and eccentric contraction, while the ligament and joint capsule on the shoulder joint are relatively weak, which also makes the joint often appear injury caused by overuse. It has been the direction of scientific research to help athletes recover their functions and return to the arena through effective rehabilitation training and prerehabilitation training. In this paper, the reliability and short-term effect of wearing dynamic and static shoulder joint brace after arthroscopic repair of rotator cuff injury were studied through a controlled trial of tennis exercise for the treatment of shoulder injury. The purpose of this study was to apply the dynamic and static shoulder joint brace to patients with rotator cuff injury and shorten the recovery time of shoulder joint function the operation. This paper also studies the therapeutic effect verification of patients with rotator cuff injury during rehabilitation period by wearing shoulder joint brace with dynamic and static combination. Through the comparison between the experimental group and the control group, it is verified that the effect of rehabilitation intervention is better than that of the control group, which shows that the use of dynamic and static shoulder joint brace can improve the range of motion of shoulder joint and patient satisfaction, and the effect increases with time. This study improves the shoulder strength of tennis players through functional training, demonstrates the value and significance of functional training for the development of tennis through experiments, and provides a reference for athletes to improve their physical fitness training. At the same time, the research content of this paper can also provide references and promotion for sports events.

Research on the Protection of Extensor and Flexor Muscles in the Waist and Back of Competitive Athletes.

In the past, in the study of special sports quality of heavy antagonistic sports events, the study of strength quality training was emphasized. The transformation of athletes' strength quality to special strength was highlighted, and the special exercises which tended to be consistent with the characteristics of wrestling events were added. However, in competition and training, athletes' spine bears a heavy load. Long-term static contraction of lumbar muscles can lead to excessive local load and injury of lumbar muscles. In this paper, the test results of athletes' joints are analyzed, and the waist protection scheme for athletes' strength training is obtained. First of all, solve the problem of athletes' action mode and improve athletes' muscle endurance. All special sports quality evaluation can reach a good level. Then, enhance athletes' explosive power. Thus, all special sports quality evaluations can reach an excellent level. It is concluded that the waist and back are the key parts to support their participation in various sports, maintain body balance, and realize power transmission. Through the study, it is found that there are significant differences in the muscle strength indexes of the maximum strength of the waist and back of athletes of different levels, which fully proves the characteristics of the maximum strength of the waist and back. Through the test, we can understand the flexion and extension strength, range, speed, force, and flexion and extension ratio of athletes' joints and take timely optimization measures according to the test results to avoid sports injuries in training. It has a key guiding significance for the measurement, analysis, and evaluation of athletes' joint muscle strength, as well as rehabilitation training after injury and prevention of reinjury.

Self-Regulating Solar Steam Generators Enable Volatile Organic Compound Removal through In Situ H2O2 Generation.

Interfacial solar steam generation for clean water production suffers from volatile organic compound (VOC) contamination during solar-to-steam conversion. Here, we present a solar steam generator based on the integration of melamine foam (MF), polydopamine (PDA), and Ag/AgCl particles. Together with the high photothermal conversion efficiency (ca. 87.8%, 1 kW/m2) achieved by the PDA thin film, the Ag/AgCl particles can efficiently activate the localized generation of H2O2 and •OH in situ, thus degrading the VOCs during the rapid vapor generation. The generation of H2O2 and •OH in situ also facilitates the creation of a buffer zone containing H2O2 and •OH for the rapid removal of organic pollutants in the surrounding water attracted to the solar vapor generator, demonstrating a self-cleaning steam generator toward various volatile compounds such as phenol, aniline, 2,4-dichlorophenol, and N,N-dimethylformamide in a wide range of concentrations.

Chiral Single-Photon Generators.

Chiral photons have the potential to advance information technologies due to their robustness in carrying binary data against noisy backgrounds as well as their capacity for constructing single-photon isolators and circulators through nonreciprocal photon propagation. In this Perspective, we highlight recent efforts to generate chiral single photons using circularly polarized light sources. We delve into possible future technologies that integrate these light sources with other active optical elements as a versatile platform for information processing.

Overdamped Antiferromagnetic Strange Metal State in Sr_{3}IrRuO_{7}.

The unconventional electronic ground state of Sr_{3}IrRuO_{7} is explored via resonant x-ray scattering techniques and angle-resolved photoemission measurements. As the Ru content approaches x=0.5 in Sr_{3}(Ir_{1-x}Ru_{x})_{2}O_{7}, intermediate to the J_{eff}=1/2 Mott state in Sr_{3}Ir_{2}O_{7} and the quantum critical metal in Sr_{3}Ru_{2}O_{7}, a thermodynamically distinct metallic state emerges. The electronic structure of this intermediate phase lacks coherent quasiparticles, and charge transport exhibits a linear temperature dependence over a wide range of temperatures. Spin dynamics associated with the long-range antiferromagnetism of this phase show nearly local, overdamped magnetic excitations and an anomalously large energy scale of 200 meV-an energy far in excess of exchange energies present within either the Sr_{3}Ir_{2}O_{7} or Sr_{3}Ru_{2}O_{7} solid-solution end points. Overdamped quasiparticle dynamics driven by strong spin-charge coupling are proposed to explain the incoherent spectral features of the strange metal state in Sr_{3}IrRuO_{7}.

Ubiquitous strong electron-phonon coupling at the interface of FeSe/SrTiO3.

The observation of replica bands in single-unit-cell FeSe on SrTiO3 (STO)(001) by angle-resolved photoemission spectroscopy (ARPES) has led to the conjecture that the coupling between FeSe electrons and the STO phonons are responsible for the enhancement of Tc over other FeSe-based superconductors. However the recent observation of a similar superconducting gap in single-unit-cell FeSe/STO(110) raised the question of whether a similar mechanism applies. Here we report the ARPES study of the electronic structure of FeSe/STO(110). Similar to the results in FeSe/STO(001), clear replica bands are observed. We also present a comparative study of STO(001) and STO(110) bare surfaces, and observe similar replica bands separated by approximately the same energy, indicating this coupling is a generic feature of the STO surfaces and interfaces. Our findings suggest that the large superconducting gaps observed in FeSe films grown on different STO surface terminations are likely enhanced by a common mechanism.

Observation of a three-dimensional quasi-long-range electronic supermodulation in YBa2Cu3O(7-x)/La0.7Ca0.3MnO3 heterostructures.

Recent developments in high-temperature superconductivity highlight a generic tendency of the cuprates to develop competing electronic (charge) supermodulations. While coupled with the lattice and showing different characteristics in different materials, these supermodulations themselves are generally conceived to be quasi-two-dimensional, residing mainly in individual CuO2 planes, and poorly correlated along the c axis. Here we observed with resonant elastic X-ray scattering a distinct type of electronic supermodulation in YBa2Cu3O(7-x) (YBCO) thin films grown epitaxially on La0.7Ca0.3MnO3 (LCMO). This supermodulation has a periodicity nearly commensurate with four lattice constants in-plane, eight out of plane, with long correlation lengths in three dimensions. It sets in far above the superconducting transition temperature and competes with superconductivity below this temperature for electronic states predominantly in the CuO2 plane. Our finding sheds light on the nature of charge ordering in cuprates as well as a reported long-range proximity effect between superconductivity and ferromagnetism in YBCO/LCMO heterostructures.