Key Tipping Point for Future Ocean Stratification Identified by IAP
A recent study led by the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, quantifies the observed strengthening of ocean stratification since the 1960s and explores its climatic implications. In a warming climate, the “lighter-above, heavier-below” layering of the ocean has intensified, a driver of planetary climate and ecosystem change. CMIP6 projections indicate a critical tipping point may occur in the 2050s–60s: under a lower-emission scenario global stratification could reverse its upward trend and begin to weaken. The work was supported by the Earth System Science Numerical Simulator Facility (EarthLab). Results appear in Nature Reviews Earth & Environment.
Source: Institute of Atmospheric Physics, Chinese Academy of Sciences
Physics Breakthrough: Ultrafast Dynamics in Topological Ferroelectrics
The Hx-Ex1 team at the Huairou Research Division of the Institute of Physics (IOP), CAS / Beijing National Laboratory for Condensed Matter Physics, led by Associate Researcher Wang Xinbo and Researcher Luo Jianlin, has achieved a major advance in the ultrafast dynamics of topological ferroelectrics. By linking macroscopic nonlinear optical responses to microscopic collective dynamics, the study unveils a new light-field mechanism for controlling matter and identifies polar skyrmions as ideal platforms for ultrafast optoelectronics. Experiments leveraged the Synergetic Extreme Condition User Facility (SECUF). The study has been published in Nature Physics.
Source: Synergetic Extreme Condition User Facility
PKU Quantum Microscope Probes Solid–Liquid Interface
Prof. Jiang Ying (Quantum Materials Science Center and Interdisciplinary Institute of Light-Elements Quantum Materials, Peking University) teamed with Prof. Meng Sheng (IOP, CAS) to develop a quantum microscope uniquely sensitive to solid–liquid interfaces. Merging scanning-probe microscopy with quantum sensing, the technique directly imaged—at nanometre resolution—electron transfer, bond breaking, and proton diffusion during water splitting. Physical Review Letters published the work; Physics magazine highlighted it as “a major advance born at the crossroads of two disciplines.”
Source: School of Physics, Peking University
Time-Reversal-Invariant Topological State Realized in Twisted Bilayer InSe
The SF09 group at the State Key Laboratory of Surface Physics, IOP / Beijing National Laboratory for Condensed Matter Physics, and collaborators have realized a time-reversal-invariant topological state in a two-dimensional van der Waals semiconductor for the first time. Twist-controlled moiré superlattices provide a new route to engineer topological quantum states, offering a physical foundation for 2-D-semiconductor-based topological devices and opening a chapter in twistronics. High-field measurements were performed at SECUF. Results appear in Nature Communications.
Source: Institute of Physics, Chinese Academy of Sciences
PKU–THU Team Fills Terahertz Gap with Electron-Microscopy Spectroscopy
Prof. Gao Peng’s group (Quantum Materials Science Center, Electron Microscopy Laboratory, and Interdisciplinary Institute of Light-Elements Quantum Materials, Peking University) collaborated with Prof. Yu Pu’s team (Department of Physics, Tsinghua University) to excite and detect phonon polaritons spanning the mid-infrared to terahertz range in free-standing SrTiO? films only a few unit-cells thick. Using scanning transmission electron microscopy–electron energy-loss spectroscopy, they achieved a compression ratio >500 and a group velocity as low as 7 × 10?? c—record optical compression and slow-wave behavior. Published in Science Advances.
Source: School of Physics, Peking University