Abstract: A new class of fundamental devices and methods for their manufacture and use. The bulk magnetic field replicators of the present invention require no precision machining or alignment to accurately reproduce magnetic fields of any complexity, nor extreme positional stability to maintain superconductivity. Such bulk devices may be formed of either low or high critical temperature superconductive materials, but are particularly adapted to formation from high critical temperature materials.
Abstract: A superconductive polycrystalline body is produced having a composition selected from the group consisting of Y.sub.1-x (Ln).sub.x Ba.sub.2 Cu.sub.3 O.sub.7-7, La.sub.1-x (Ln).sub.x Ba.sub.2 Cu.sub.3 O.sub.7-y and a combination thereof wherein x ranges from about 0.01 to about 0.5, y ranges up to about 0.3, and where Ln is selected from the group consisting of Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb and a combination thereof.