Reentrant superconductivity at an oxide heterointerface.

Maryenko, Denis; Kawamura, Minoru; Maznichenko, Igor V; Ostanin, Sergey; Zhang, Ding; Kriener, Markus; Dugaev, Vitalii K; Sherman, Evgeny Ya et al. · Sci Adv · 2026

basic_science · Level V

Where this comes from

Abstract

A magnetic field typically suppresses superconductivity by either breaking Cooper pairs via the Zeeman effect or inducing vortex formation. However, under certain circumstances, a magnetic field can stabilize superconductivity instead. This seemingly counterintuitive phenomenon is associated with magnetic interactions and has been extensively studied in three-dimensional materials. By contrast, this phenomenon, hinting at unconventional superconductivity, remains largely unexplored in two-dimensional systems, with moiré-patterned graphene being the only known example. Here, we report the observation of reentrant superconductivity at the epitaxial (110)-oriented LaTiO<sub>3</sub>-KTaO<sub>3</sub> interface. This phenomenon occurs across a wide range of charge carrier densities, which, unlike in three-dimensional materials, can be tuned in situ via electrostatic gating. We propose that the observed reentrant superconductivity can arise from an interplay between strong spin-orbit coupling and a magnetic field-driven modification of the Fermi surface. Our findings provide insight into reentrant superconductivity and establish a robust platform for exploring unconventional superconducting phenomena in two-dimensional systems.