séminaire conjoint LSI+CPHT+PMC = M4S

Séminaire conjoint LSI+CPHT+PMC = M4S

Mardi 27 mai 11h00

Salle de conférence Louis Michel (CPHT)

Benoît Fauqué
(Chargé de Recherche CNRS, LPEM, ESPCI (Paris))

Ferroelectric fluctuations shape the superconducting dome of SrTiO₃

Superconducting domes, ubiquitous across a variety of quantum materials, are often understood as a favored window for pairing, opened by fluctuations of competing orders that induce a peak in the doping evolution of the superconducting transition temperature. Yet, a quantitative understanding of how such a window closes remains lacking. In this talk, I will discuss the case of the superconducting dome in doped SrTiO₃. In contrast to other families, the parent compound is not magnetic but instead is a quantum paraelectric, characterized by a large dielectric constant (ε ≈ 20,000). I will show that its superconducting dome arises from the interplay between the increase in the density of states and the inevitable collapse of the quantum paraelectric phase—both induced by doping. I will also discuss the remarkable transport properties, such as a linear, quasi-isotropic magnetoresistance, which we observe as the quantum paraelectric phase dies off.