A simple superconducting system which allows almost loss-less ac magnetic field to be generated in the kilo-oested region and in the frequency range from dc up to more than 1 kHz is described. The behaviour of commercially available superconducting wires and the influence of winding of the coils are also considered.
van de Klundert, L. J. M., Bos, M. R. E., & van der Marel, L. C. (1977). A loss-less superconducting kilo-oersted ac magnetic field system. Cryogenics, 17(3), 157-160. https://doi.org/10.1016/0011-2275(77)90276-4