Enhanced Critical Field of Superconductivity at an Oxide Interface

Thenature of superconductivity and its interplay with strong spin-orbitcoupling at the KTaO3(111) interfaces remain a subjectof debate. To address this problem, we grew epitaxial LaMnO3/KTaO3(111) heterostructures. We show that superconductivityis robust against the in-plane magnetic field, with the critical fieldof superconductivity reaching & SIM;25 T in optimally doped heterostructures.The superconducting order parameter is highly sensitive to the carrierdensity. We argue that spin-orbit coupling drives the formationof anomalous quasiparticles with vanishing magnetic moment, providingsignificant condensate immunity against magnetic fields beyond thePauli paramagnetic limit. These results offer design opportunitiesfor superconductors with extreme resilience against the applied magneticfields.

Automated summary

In this study, epitaxial LaMnO3/KTaO3(111) heterostructures were grown to investigate the nature of superconductivity under in-plane magnetic fields. It was found that superconductivity remains robust in optimally doped heterostructures, with a critical field of approximately 25 T. The superconducting order parameter is highly sensitive to carrier density. The formation of anomalous quasiparticles with vanishing magnetic moment, driven by spin-orbit coupling, provides significant immunity against magnetic fields beyond the Pauli paramagnetic limit. These findings present opportunities for designing superconductors with extreme resilience against applied magnetic fields.