Magnetic coupling between mesoscopic superconducting rings

Abstract

Using the nonlinear Ginzburg-Landau theory we investigated the dependence of the magnetic coupling between two concentric mesoscopic superconducting rings on their thickness. The size of this magnetic coupling increases with the thickness of the rings.

Stable and metastable states in a mesoscopic superconducting “eight” loop in presence of an external magnetic field

“…Note that the maximum value of p max for the thermodynamically stable state of our systems (A − C) is the same: 1/2(R 1 + R 2 ). The two rings in our "eight" loop are strongly coupled and as a result the Gibbs free energy of this system is not simply the sum of the energies of two uncoupled rings plus a small interaction term as for the case of two magnetically coupled rings 5,6 . In Fig.…”