Design and Tests of the 100-T Triple Coil at LNCMI

The Laboratoire National des Champs Magnétiques Intenses (LNCMI) is a French host facility for experiments in high magnetic fields. Based on two sites, the LNCMI offers routinely static magnetic fields up to 36 T at its Grenoble site, and pulsed magnetic fields up to 90 T using nondestructive magnets and up to 180 T using single-turn magnets at its Toulouse site. Internal research is carried out in the lab and experiment time is allocated to external researchers. LNCMI is a founding member of the European Magnetic Field Laboratory with the Hochfeld-Magnetlabor in Dresden (HLD) and High Field Magnet Laboratory in Nijmegen. The LNCMI develops all the instrumentation required by experiments in high magnetic fields, in particular, the electromagnets that generates these high fields. The main difficulty in generating a very high magnetic field in a nondestructive way is to contain the huge stresses on the magnet conductors due to the Lorentz forces. We present here the design and first operation of a new type of pulsed magnet consisting of three nested coils energized with three independent capacitor banks. This triple coil, unique in the world and associated with the most powerful generators of the LNCMI, reached a peak field value of 98.8 T and permitted the LNCMI to break the European record for the nondestructive pulsed magnetic fields established at 95.6 T in October 2016 by HLD. The next objective is to go beyond the symbolic value of 100 T and the world record of 100.75 T held by the Los Alamos National Laboratory since June 2012. We will describe the next steps toward this goal and some ways to go beyond, keeping in mind that this magnet is above all else a tool for scientific research, in particular to explore the fundamental properties of the matter.