Electromagnetics of Superconductor/Paramagnet Heterostructures

Conditioning of magnetic fields is a novel route to improve type-II superconductor performance in high-current and high-field applications directed at increasing the current-carrying capability and the critical fields of superconductor/paramagnet heterostructures, as well as reducing their hysteretic AC loss. Through a methodical analysis and noteworthy solutions, Electromagnetics of Superconductor/Paramagnet Heterostructures presents a phenomenological account of the remarkable electromagnetic properties of superconductor paramagnet heterostructures, as captured by Maxwell's electrodynamics, generalized London theory, and Bean's model of the critical state. Beginning with the introduction of the basic concepts of superconductivity which are necessary for understanding of the following studies, exact closed-form solutions are revealed for a range of idealized heterostructures. Investigations of the superconductor constituents primarily focus on strips or tapes, filaments and tubes, with a transport current imposed or a magnetic field applied. Geometrical as well as materials aspects of both the magnetic shielding effect and the hysteretic AC loss undergo detailed analysis which permits identification of the conditions for non-dissipative critical, or even overcritical, states to exist. Crucial issues such as the barrier against the penetration of magnetic flux at superconductor/paramagnet interfaces or the nucleation of magnetic vortex loops equally find their place. Finally, based on the magnetostatic-electrostatic analogues, the finite-element simulations of the Meissner state and the critical state of thin superconductors in paramagnetic environments of arbitrary shape and permeability are performed. This presents an effective tool for designing superconductor/paramagnet heterostructures.