Investigation of methods for combining several trapped field superconducting magnets to obtain large magnetic field gradients 

M. Michel Houbart will publicly defend his thesis entitled "Investigation of methods for combining several trapped field superconducting magnets to obtain large magnetic field gradients".

Summary

The context of this project is the design of compact systems for generating large magnetic field gradients over length scales of a few centimetres. Methods relying on ferromagnetic materials are limited by their intrinsic magnetic saturation. The strategy followed to generate stronger gradients with the same volume of material or less is to use superconducting materials. In this case, persistent current loops of the order of 100 kA / cm² can be induced and trapped permanently in the superconductor. Such ‘trapped field magnets’ can generate fields that are much stronger than the saturation magnetization of ferromagnets.

Although the properties of individual trapped field magnets magnetized separately are well documented, there is little scientific information on their magnetic behaviour when several of them are brought in close vicinity. The goal of this thesis is to determine how several trapped field magnets with non-parallel magnetization directions can be combined efficiently to generate large magnetic field gradients and to surpass the limits of ferromagnetic materials.

The innovative aspect of this research lies in exploiting the benefits of assembling mechanically several superconductors, either pre-magnetized or placed in a large background field, while overcoming the associated forces and torques. In view of understanding the physical mechanisms arising in such structures, the study will be carried out both experimentally and theoretically.

Practical information

Defence will take place on Wednesday March 20th at 14:30, to all at at Institut de Montefiore (salle R7, Bât. B28 - Sart Tilman) and via FSA PhD Channel.