The magnetic field optimization of RE-Ba-Cu-O (REBCO,
RE=rare earth) bulk superconducting undulators is a fundamental step toward their implementation in an accelerator driven photon source, like a synchrotron or a free electron laser. In this article, we propose a sorting algorithm to reduce the undulator’s phase error based on the reconstruction of the trapped current inside the bulks of a staggered array undulator. The results obtained with a YBCO short prototype field-cooled down to 10 K in a 10 T magnetic field are reported. Finally, its performance is critically discussed in light of 2D magnetic field maps of its individual components, obtained at
LN2 after the magnetization tests. Published by the American Physical Society 2024