Hysteretic method for measuring the flux trapped within the core of a   superconducting lead-coated ferromagnetic torus by a linked superconducting   tin ring, in a novel Aharonov-Bohm-like effect based on the Feynman   path-integral principle
  A novel kind of nonlocal, macroscopic Aharonov-Bohm effect involving two topologically linked superconducting rings made out of two different materials, namely, lead and tin, is suggested for experimental observation, in which the lead ring is a torus containing a core composed of permanently magnetized ferromagnetic material. It is predicted that the remnant fields in a hysteresis loop induced by the application of a magnetic field imposed by a large external pair of Helmholtz coils upon the tin ring, will be asymmetric with respect to the origin of the loop. An appendix based on Feynman's path-integral principle is the basis for these predictions. 
Raymond Chiao
quant-ph