Zusammenfassung
Hybrid nanostructures not only open new routes for studying the coexistence of superconductivity and ferromagnetism, but they also provide new insights into the fundamentals of quantum electronics. We have investigated, by a series of experiments, the chan-e in the superconducting wavefunction resulting from the interaction between the spins of a Cooper pair and the exchange field. Tunneling ...
Zusammenfassung
Hybrid nanostructures not only open new routes for studying the coexistence of superconductivity and ferromagnetism, but they also provide new insights into the fundamentals of quantum electronics. We have investigated, by a series of experiments, the chan-e in the superconducting wavefunction resulting from the interaction between the spins of a Cooper pair and the exchange field. Tunneling spectroscopy reveals an inhomogeneous Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting state induced in a ferromagnetic thin film by the proximity effect. As a consequence, critical current and macroscopic quantum interference (SQUID) experiments show pi-coupling between two superconductors coupled through a ferromagnetic thin film. pi-coupling origmates a spontaneous half quantum flux in a superconducting ring. This phase transition has been observed by Josephson and Hall magnetometry. (c) 2006 Academie des sciences. Published by Elsevier SAS. All rights reserved.