​After exploring the “Kondo effect,” which describes the behavior of magnetic atoms in certain metals, Jacques Flouquet (Emeritus Research Director at the CNRS, Pheliqs Laboratory – CEA-Irig) studied materials containing cerium or uranium, in which electrons interact strongly. His work has led to a better understanding of their magnetic properties at very low temperatures, particularly under the influence of a magnetic field or pressure. He has also demonstrated the existence of several superconducting phases in the UPt₃ (platinum-uranium) compound, the coexistence of superconductivity and ferromagnetism in UGe₂ (uranium digermanide) and URhGe (uranium-rhodium-germanium), and he is currently studying the compound UTe₂ (uranium ditelluride), which also exhibits different superconducting phases under strong magnetic fields. Finally, his research on solid-state helium-3 has led to the direct observation of its antiferromagnetic phase at temperatures below one millikelvin.

© Académie des Sciences​/Mathieu Baumier​