中国“人造太阳”实验找到突破密度极限的方法

Core Insights - The research team from the Hefei Institute of Physical Science, Chinese Academy of Sciences, confirmed the existence of a density-free zone in the EAST (Experimental Advanced Superconducting Tokamak) nuclear fusion device, providing significant physical evidence for high-density operation in magnetic confinement fusion devices [1][6] Group 1: Tokamak Device and Density Limit - The Tokamak device utilizes magnetic confinement to achieve controlled nuclear fusion, with plasma density being a critical parameter that directly affects fusion reaction rates [3] - Previous research indicated a density limit where plasma would break and escape magnetic confinement, releasing significant energy and impacting device safety [3] Group 2: Research Findings and Theoretical Models - The research team developed a boundary plasma-wall interaction self-organization (PWSO) theoretical model, identifying the key role of radiation instability caused by boundary impurities in triggering the density limit [5][6] - By utilizing a fully metallic wall environment in EAST, researchers employed methods such as electron cyclotron resonance heating and pre-filling to reduce boundary impurity sputtering, actively delaying the onset of the density limit and plasma disruption [6] Group 3: Experimental Validation and Collaboration - The experimental results aligned closely with PWSO theoretical predictions, marking the first confirmation of the existence of a Tokamak density-free zone [6] - This innovative work was a collaborative effort involving the Hefei Institute of Physical Science, Huazhong University of Science and Technology, and Aix-Marseille University, supported by the National Magnetic Confinement Fusion Program [6]