Sachio Komori - Inverse proximity effect at oxide superconductor/ferromagnet interfaces

The inverse proximity effect at a superconductor/ferromagnet interface introduces a magnetic exchange field in the superconductor (S) which locally Zeeman-splits the superconducting density of states in S close to the interface. The effect of magnetic exchange fields on superconductivity has been thoroughly explored at S/ferromagnetic insulator (S/FI) interfaces for isotropic s-wave S and a thickness that is smaller than the superconducting coherence length. I will talk about an inverse proximity effect at an all-oxide S/FI interface involving the anisotropic d-wave high temperature superconductor praseodymium cerium copper oxide (PCCO) and the FI praseodymium calcium manganese oxide (PCMO). The magnetic exchange field in PCCO, detected via magnetotransport measurements through the superconducting transition, is localized to the PCCO/PCMO interface with a magnitude that depends on the presence or absence of magnetic domain walls in PCMO. These results are promising for the development of all-oxide S/FI devices.