Numerical Modeling and Design Optimization of a MgB ₂ Bulk Superconducting Undulator

In 2023, researchers from the University of Cambridge and the Paul Scherrer Institute (PSI) successfully demonstrated the feasibility of employing second-generation high-temperature superconducting (HTS) RE-Ba-Cu-O(REBCO) materials for undulator applications, achieving a magnetic field of 2.1 T with a 10 mm period and a 4 mm magnetic gap. This remarkable performance is primarily attributed to the high critical current density (<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">J_c</i>) of REBCO. However, REBCO also presents several challenges, including high production cost, complex fabrication procedures, and limited machinability. In contrast, although MgB₂ exhibits a lower <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">J_c</i>, it offers advantages such as ease of synthesis and machining, making it a promising candidate for undulator development. This study presents the design, preparation fabrication, and assembly of short-period MgB₂ bulk undulators, utilizing spark plasma sintered (SPS) MgB₂ bulks with a 16 mm period and a 4 mm magnetic gap, after 2D size optimization and 3D simulation, it is estimated that an undulator magnetic field of 1.75 T will be generated.