High-field-stabilized reentrant superconductivity in infinite-layer nickelate thin films

Magnetic fields typically suppress superconductivity through Pauli and orbital limiting effects. However, there are rare instances of magnetic-field-induced superconductivity, as observed in Chevrel-phase compounds, organic conductors, uranium-based heavy-fermion systems, and moiré graphene-although these materials possess inherently low superconducting transition temperatures (T_c). Here, we demonstrate high-field-stabilized superconductivity in a class of materials recently shown to have significantly higher T_c values (up to 40 K): the infinite-layer nickelates. We show that both the low-field and high-field superconducting states can be understood in terms of a field-compensation mechanism, better known as the Jaccarino-Peter effect. These findings demonstrate the possibility of achieving substantially enhanced upper critical fields in high-temperature superconductors.