Triplet odd-frequency superconductivity in hybrid superconductor–ferromagnet structures

We present an overview of the contributions made by Konstantin B. Efetov and the authors to the field of triplet odd-frequency superconductivity in hybrid ferromagnet–superconductor structures (Bergeret et al., 2005) and the repercussions they had on experimental and theoretical research. Konstantin B. Efetov passed away in August 2021. We hope the present short review gives a faithful testimony of an important part of his scientific legacy.