Combining superconducting and ferromagnetic materials to make a magnetic cloak
Fedor Gömöry
Institute of Electrical Engineering
Slovak Academy of Sciences
Abstract:
A magnetic shield is a device used to prevent a magnetic field to come in contact with an object located inside the shield. Such a shield can be made of conventional ferromagnetic material, normal metal (in AC regime), or superconducting material. However, some composite structures behave in a very interesting way, for instance when one covers a superconducting shield with a ferromagnetic layer: the ferromagnetic layer allows absorbing the magnetic flux expelled from the space shielded by the superconductor, resulting in a so-called 'magnetic cloak”. Indeed, this special type of shield acts only on the objects in its interior, but seen from the external world, the flux lines show no distorsion at all, and the cloak is thus “invisible' for a magnetic field detector. Experimental research combined with electromagnetic modeling revealed the possibility of utilizing for this purpose rather common materials, i.e. the 2nd generation high temperature superconducting tapes, combined with epoxy/ferrite composites. The presentation will discuss possible ways of improving the cloak performance and present potential applications of this novel superconducting device.
Bio: Fedor Gömöry is research professor in the field of applied superconductivity at the Institute of Electrical Engineering of the Slovak Academy of Sciences in Bratislava, Slovakia. The group participated in several European projects dedicated to the development of electric power devices from the second generation of HTS tapes. His current activities focus on the development of numerical simulation techniques for composite superconducting wires and optimization of the wire architecture from the point of AC losses.
Cette conférence est présentée par le RQMP Versant Nord du Département de physique de l'Université de Montréal et de Génie physique de la Polytechnique.
