Tunable Superconductivity at the Surface of Single-Crystal Ferroelectric Laser-Irradiated Lithium Tantalites.

Complex oxides exhibit abundant unique physical properties and quantum effects, making them an ideal platform for exploring multifunctional coupling properties. Despite significant efforts, achieving metal conductivity, even superconductivity, on the ferroelectric surface still remains challenging. Here, we realize metallicity on the surface of ferroelectric LiTaO₃ through laser irradiation, with in situ monitoring of dynamic resistance. More intriguingly, the superconductivity and its tunability are discovered in the temperature range of 2.30-3.20 K, with an estimated Ginzburg-Landau coherence length of ∼7.24 nm. The superconductivity originates from Ta-related nanoparticles during the percolation process, which is revealed by scanning transmission electron microscopy and low-temperature transport measurements with the variation of air pressure, laser pulse number, and crystal orientation. Our findings pave an avenue for investigating the underlying mechanism of superconductivity in complex oxides through laser-matter interactions, which would contribute to the understanding and practical applications of ferroelectric superconductivity.