Institute of Physics Discovers Intrinsic Nonlinear Effect in Josephson Junctions Leading to Disappearance of First-Order Shapiro Step

Recently, a research team led by Lyu Li at the Institute of Physics, Chinese Academy of Sciences (CAS), discovered that the intrinsic nonlinear current-voltage characteristics of Josephson junctions alone can lead to the disappearance of the first-order step, accompanied by a unique “sawtooth-shaped” transition boundary. This study reveals sawtooth-shaped transition line features that cannot be explained by the conventional resistively and capacitively shunted junction (RCSJ) model, demonstrating that the intrinsic nonlinear effect of the junction is a universal mechanism for generating switching jumps and the disappearance of the first Shapiro step. This work provides a new perspective for re-examining a large number of topological Josephson junction experiments and demonstrates the possibility of manipulating the Shapiro step spectrum by tuning the nonlinearity of the junction. In this study, the C1 Sub-millikelvin Experimental Station and the C4 Electron Spectroscopy Experimental Station at the Synergetic Extreme Condition User Facility (SECUF) played a critical role. The results were published in Communications Physics.

Source: Synergetic Extreme Condition User Facility (SECUF)

Institute of Atmospheric Physics Proposes a Regional-Industrial Park Multi-Scale Collaborative Air Quality Modeling Framework

Recently, Wang Tao, Li Jie, Wang Zifa, and collaborators at the Institute of Atmospheric Physics, Chinese Academy of Sciences (CAS), proposed the IAQMS-Industry regional-industrial park multi-scale air quality modeling framework, aiming to address the long-standing issues of cross-scale consistency and insufficient industrial emission resolution in the field of air quality modeling. The core innovation of IAQMS-Industry lies in constructing a multi-scale collaborative simulation system integrating regional background fields, urban-scale chemical transport, and point-source plume diffusion, achieving cross-scale simulation from the regional level down to the industrial park level. The proposal of IAQMS-Industry provides a new technical pathway for future refined pollution simulation, emission analysis, and multi-scale coupling research in industrial parks, and also lays the foundation for building higher-resolution industrial emission databases and improving regional model performance. This work was supported by the Earth System Science Numerical Simulator Facility (EarthLab), and the research results were published in Journal of Environmental Sciences.

Source: Earth System Science Numerical Simulator Facility (EarthLab)

Institute of Physics Designs and Builds All-Solid-State Magnetocaloric Refrigeration Device for Thermal Management

Recently, a team from the Institute of Physics, Chinese Academy of Sciences (CAS) / Beijing National Laboratory for Condensed Matter Physics, State Key Laboratory of Magnetism, and collaborators built the world’s first all-solid-state magnetocaloric refrigeration device for thermal management, utilizing the novel principle of hybrid regenerative heat exchange and the concept of replacing liquid with highly thermally conductive solids for regeneration. This work employs highly thermally conductive solid-state heat transfer media and a hybrid regenerative mode to construct the first all-solid-state magnetocaloric refrigeration device capable of providing point-to-point effective thermal management for electronic devices. The experiments demonstrate the tremendous application potential and engineering feasibility of all-solid-state magnetocaloric refrigeration devices in thermal management, offering a new method for electronic device thermal management and a new development pathway for magnetocaloric refrigeration. This work was supported by the Synergetic Extreme Condition User Facility (SECUF), and the results were published in Proceedings of the National Academy of Sciences of the United States of America.

Source: Institute of Physics, Chinese Academy of Sciences (CAS)

Institute of Physics Conducts Systematic Study of Light-Induced Bimerons in Chiral Magnets

Recently, a team from the Institute of Physics, Chinese Academy of Sciences (CAS) / Beijing National Laboratory for Condensed Matter Physics, Laboratory of Advanced Materials and Structure Analysis, systematically studied laser-induced magnetic bimerons in the chiral magnet Co₈Zn₈Mn₄ through comprehensive technical means including Lorentz transmission electron microscopy, femtosecond laser pulse excitation, and positive/negative magnetic field regulation. The study found that under room-temperature conditions, laser pulses of specific energy can excite and induce the generation of two Bloch-type bimeron states with different chiralities. This research validates the scheme of using laser pulses to control topological magnetic domain structures under in-plane magnetization backgrounds, establishing an efficient optical single-pulse manipulation technique; it also provides new ideas for the design of room-temperature spintronic devices and has important guiding significance for constructing next-generation spintronic memory and logic devices. The experiments were conducted at the D4 Ultrafast Electron Microscopy Experimental Station of the Synergetic Extreme Condition User Facility (SECUF), and the research results were published in Nature Communications.

Source: Institute of Physics, Chinese Academy of Sciences (CAS)

Institute of Atmospheric Physics Proposes an AI-Driven Integrated Weather-Health Prediction System

Recently, the Institute of Atmospheric Physics, Chinese Academy of Sciences (CAS), and collaborators proposed an AI-driven integrated weather-health prediction system, aiming to directly transform meteorological forecast information into health risk assessments and push the warning system to transition from “predicting weather” to “predicting health.” The study points out that artificial intelligence provides a new technical pathway for bridging the critical gap between weather forecasting and health risk prediction. The research shows that this framework can be widely applied to various extreme weather scenarios. By integrating meteorological forecasts, environmental observations, climate models, and population data, artificial intelligence can construct a complete prediction chain from weather drivers to environmental exposure and then to health impacts. The research results were published in The Innovation.

Source: Earth System Science Numerical Simulator Facility (EarthLab)

National Space Science Center Achieves Advances in Ground-Space Equivalence for Dynamic Risk Assessment of Single-Event Effects

Recently, a team from the Space Weather Effects Center of the State Key Laboratory of Solar Activity and Space Weather at the National Space Science Center, Chinese Academy of Sciences (CAS), in collaboration with the State Key Laboratory of Space Environment Detection, achieved a series of advances in ground-space equivalence research for dynamic risk assessment of single-event effects. This series of studies formed a continuous research chain from on-orbit particle detection, measured analysis of single-event upset (SEU) inducing factors, to dynamic risk quantitative assessment, covering low-orbit proton-dominated SEU scenarios and medium-to-high-orbit galactic cosmic ray-dominated radiation environments. The findings provide theoretical support for understanding the interaction between the space radiation environment and electronic device response, as well as for single-event risk assessment and space weather effects analysis. The research results were published in IEEE Transactions on Nuclear Science.

Source: National Space Science Center, Chinese Academy of Sciences (CAS)

National Space Science Center Proposes New Method for Intelligent Identification and Localization of Space Hurricanes

Recently, a team from the State Key Laboratory of Solar Activity and Space Weather at the National Space Science Center (NSSC) and collaborators proposed a set of deep learning-based automatic identification and high-precision localization methods for “space hurricanes.” The research team screened 570 real “space hurricane” events from 300,000 far-ultraviolet auroral observation images from the LMSD satellite as “positive samples” (images containing “space hurricanes”). An equal number of “negative samples” (ordinary auroral images without “space hurricanes”) were also added to the dataset, specifically including “easily confused negative samples” that are very similar in shape to typical space hurricanes. Through this approach, the model can provide high accuracy under complex and variable auroral scenarios. This achievement provides an efficient and objective tool for “space hurricane” identification and lays the foundation for polar region space weather modeling and risk assessment. This work was supported by the Meridian Project, and the research results were published in Space Weather.

Source: National Space Science Center, Chinese Academy of Sciences (CAS)