At 21:00 on April 12, 2023, China's all-superconducting tokamak nuclear fusion experimental device (EAST), known as the "artificial sun", set a new world record and successfully achieved steady-state high-constraint mode plasma operation for 403 seconds. This event is of great significance for exploring the frontier physical problems of future fusion reactors, improving the economy and feasibility of nuclear fusion energy, and accelerating the realization of fusion power generation. It is reported that there are more than 200 core technologies and more than 2,000 patents on the EAST device. It brings together cutting-edge technologies such as "ultra-high temperature", "ultra-low temperature", "ultra-high vacuum", "ultra-strong magnetic field" and "ultra-high current" in the device, with millions of components working together. This successful breakthrough is inseparable from the improvement of plasma control, heating, wall treatment, advanced diagnosis and other technologies and the improvement of the inner vacuum chamber. (Source: Xinhua News Agency)