Recent breakthroughs have been made in the application of radio frequency (RF) superconductivity using niobium tin (Nb3Sn) materials by the Institute of Modern Physics, Chinese Academy of Sciences, and the Dongjiang Laboratory. The developed Nb3Sn solid-state conduction-cooled superconducting electron accelerator has achieved stable beam operation for the first time internationally. This accelerator's development has been supported by various projects, including the National Major Scientific and Technological Infrastructure Project, the National Natural Science Foundation of China, the "Youth Promising Talent" program of the Chinese Academy of Sciences, and the research platform of the Guangdong Provincial Laboratory of Advanced Energy Science and Technology.
A team of experts from the Institute of High Energy Physics, Tsinghua University, Peking University, University of Science and Technology of China, Sichuan University, and the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, listened to the project team's development and testing reports and conducted on-site testing of the solid-state conduction-cooled Nb3Sn superconducting electron accelerator. The maximum energy of the accelerated electron beam reached 4.6 MeV, with a macro-pulse current intensity exceeding 100 mA.
The superconducting transition temperature of Nb3Sn material is twice that of metallic niobium, making it a key breakthrough direction for the next generation of RF superconducting materials and a frontier research hotspot and competitive high ground in the RF superconductivity field. The application of Nb3Sn can significantly reduce thermal load, improve the operating temperature of RF superconducting accelerators, and simplify system complexity. It not only reduces the demand and operating costs of superconducting accelerators for large-scale cryogenic systems but also promotes the miniaturization and industrialization of RF superconducting accelerators.
Since 2018, the Institute of Modern Physics has been at the forefront of Nb3Sn RF superconducting technology research in China, achieving the full process from equipment and mechanisms to processes of Nb3Sn superconducting film. After 2022, with the support of the research platform project of the Guangdong Provincial Laboratory of Advanced Energy Science and Technology, the team completed key technological breakthroughs in the systematic integration and application of Nb3Sn RF superconducting technology, and for the first time internationally, successfully developed and achieved stable beam operation of the solid-state conduction-cooled Nb3Sn superconducting electron accelerator.
This achievement provides a demonstration and verification for the systematic integration of Nb3Sn superconducting accelerators and stable beam acceleration, which is of great significance for China to transition from following and keeping pace to leading in the field of next-generation RF superconducting technology. It helps China seize the historical opportunity of practical application in the RF superconductivity field, move away from liquid helium constraints, and occupy the technological peak in the industrial accelerator field. It also has broad application prospects in environmental protection such as wastewater and gas treatment, national security fields such as special detection equipment, medical and health fields such as isotope production, and agricultural and biological fields such as preservation and sterilization.
Solid-State Conduction Cooled Niobium Tin Electronic Superconducting Accelerator. Image provided by the Modern Physics Research Institute.
