  The electrical and structural properties of Co40Fe40B20 (CoFeB) alloy are
tunable with thermal annealing. This is key in the optimization of CoFeB-based
spintronic devices, where the advantageously low magnetic coercivity, high spin
polarization, and controllable magnetocrystalline anisotropy are utilised. So
far, there has been no report on superconducting devices based on CoFeB. Here,
we report Nb/CoFeB/Nb Josephson devices and demonstrate an enhancement of the
critical current by up to 700% following thermal annealing due to increased
structural ordering of the CoFeB. The results demonstrate that CoFeB is a
promising material for the development of superconducting spintronic devices.
