Development of Short-Period Nb3Sn Superconducting Planar Undulators

NbTi-based superconducting undulators (SCUs) have been developed and proven to increase the brightness by an order of magnitude at high X-ray energies at the ANL's Advanced Photon Source (APS). Nb
₃
Sn has the potential to further enhance the performance of SCUs. A new project, aiming to fabricate a full-length, 3-m-long Nb
₃
Sn SCU, compatible with the storage ring, has started at the APS. To develop the technology, three Nb
₃
Sn short prototype magnets were fabricated and tested in liquid helium. These prototypes were used to incrementally improve the original design. The final short model magnet reached 100% of the short sample limit. The achieved current level in this magnet is 75% higher than what an NbTi wire can deliver.