Anisotropic superconductivity at KTaO3(111) interfaces

A two-dimensional, anisotropic superconductivity was recently found at the KTaO3(111) interfaces. The nature of the anisotropic superconducting transition remains a subject of debate. To investigate the origins of the observed behavior, we grew epitaxial KTaO3(111)-based heterostructures. We show that the superconductivity is robust against the in-plane magnetic field and violates the Pauli limit. We also show that the Cooper pairs are more resilient when the bias is along [112] (I parallel to [112]) and the magnetic field is along [110] (B parallel to [110]). We discuss the anisotropic nature of superconductivity in the context of electronic structure, orbital character, and spin texture at the KTaO3(111) interfaces. The results point to future opportunities to enhance superconducting transition temperatures and critical fields in crystalline, two-dimensional superconductors with strong spin-orbit coupling.

Automated summary

A two-dimensional, anisotropic superconductivity was found at the KTaO3(111) interfaces, which violates the Pauli limit and is robust against in-plane magnetic field. The study shows that the Cooper pairs are more resilient when the bias is along [112] and the magnetic field is along [110]. The anisotropic nature of superconductivity is discussed in the context of electronic structure, orbital character, and spin texture at the KTaO3(111) interfaces.