Julien Varignon

Julien Varignon is a researcher at the CRISMAT Laboratory (CNRS UMR 6508) affiliated with ENSICAEN in Caen, France. His work focuses on phonon-mediated superconductivity in complex oxides, particularly Ruddlesden-Popper phase materials like bismuthates, antimonates, nickelates, and ruthenates. Using parameter-free density functional theory (DFT) simulations, he investigates electron-phonon coupling mechanisms, charge/orbital order, and the emergence of superconductivity in doped systems. His research bridges fundamental quantum physics and applied material science, aiming to unify understanding of superconducting mechanisms in complex oxides.

His recent seminar at LPEM (ESPCI Paris) highlighted computational findings linking insulating phases to superconducting states, emphasizing the role of structural distortions and spin formation in modulating critical temperatures (Tc). This aligns with broader efforts to discover high-Tc superconductors beyond cuprates.