Introduction to Bi‑2212 conductor and coil technology at MagLab

Slowly but steadily, HTS magnet technology is gaining clear advantages over traditional low‑temperature superconducting (LTS) technology. Thanks to their higher critical magnetic‑field limits above 25 T, HTS conductors are the only viable option for ultra‑high‑field magnets beyond 26 T. Currently, ReBCO conductors are driving much of the global advancement in HTS magnet technology. For example, Bruker recently announced a 1.3 GHz NMR system that integrates both HTS and LTS magnet technologies to achieve a magnetic field of 30.5 T. Likewise, as Commonwealth Fusion Systems continues to establish itself as a leader in this field, the worldwide demand for reliable, clean power generation for AI data centers is driving rapid advancements in HTS fusion reactors and ReBCO cable technologies.

Since the start of the 32 T all‑superconducting magnet development in 2009, the National High Magnetic Field Laboratory (MagLab) at Florida State University has been committed to advancing hybrid LTS/HTS magnet systems. Building on that success, MagLab is now developing a ReBCO/LTS hybrid 40 T magnet system funded by the U.S. National Science Foundation. In parallel, the MagLab—through the Applied Superconductivity Center—continues to pursue research on Bi-2212 technology as another strong candidate for next‑generation HTS magnet technology.

Although both ReBCO and Bi‑2212 are copper‑oxide (cuprate) superconductors, they exhibit fundamentally different characteristics due to their fabrication methods. ReBCO is produced as a thin‑film superconductor deposited on multiple buffer layers atop a robust substrate, resulting in a high‑strength tape geometry. In contrast, Bi‑2212 is produced by the traditional powder‑in‑tube process, forming a true multifilament HTS round wire with micrometer‑scale filaments embedded in a soft silver matrix.

Starting from these fundamental differences, this talk summarizes the strengths and weaknesses of Bi‑2212 as a magnet conductor, the MagLab’s R&D efforts in advancing Bi‑2212 technology, and the ongoing collaborative activities surrounding Bi‑2212 at the MagLab. To support and inspire early‑career HTS technology researchers, the final portion of the talk discusses how magnet developers could approach both Bi‑2212 and ReBCO conductors for their research areas within the broader landscape of next‑generation magnet design.