2026-06-25 理化学研究所
酸化物界面の2次元電子系とリエントラント超伝導現象の概念図
＜関連情報＞
- https://www.riken.jp/press/2026/20260625_1/index.html
- https://www.science.org/doi/10.1126/sciadv.aeg0460
酸化物ヘテロ界面における再入型超伝導 Reentrant superconductivity at an oxide heterointerface
Denis Maryenko, Minoru Kawamura, Igor V. Maznichenko, Sergey Ostanin, […] , and Masashi Kawasaki
Science Advances Published:24 Jun 2026
DOI:https://doi.org/10.1126/sciadv.aeg0460
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 LaTiO3-KTaO3 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.
