Innovative 3D Printed Nb47Ti superconducting microwave cavity: manufacturing and performance

This study investigates additive manufacturing of Nb47Ti (wt%) superconducting microwave cavities via Laser Powder Bed Fusion (LPBF) using in-situ alloying, aiming to expand the design and functional possibilities for cryogenic and quantum technologies. Post-processing heat-treatments facilitated the transformation of ω-phase into finely dispersed α-Ti precipitates, enhancing flux pinning. Magnetic characterisation confirmed a superconducting transition temperature (Tc) of 9.5 K and a critical current density (Jc) of 11.9 kA/mm² at 4.2 K and 5 T Q-factor measurements of the TE011, TE111, and TM111 modes revealed sharp transitions below Tc, with loaded Q-factors reaching 4.6 × 10⁵, 6.3 × 10⁵, and 0.61 × 10⁵, respectively. Magnetic field measurements demonstrated the cavity's shielding capabilities, with Q-factor degradation observed beyond 0.24 T at 4 K and 0.32 T at mK temperatures, indicating a robust critical magnetic field (Hc). LPBF enables producing superconducting structures with superior magnetic shielding for advanced accelerators, detectors, and quantum systems.<p></p>