title: Josephson pi state in a ferromagnetic insulator.
abstract: We predict anomalous atomic-scale 0-pi transitions in a Josephson junction with a ferromagnetic-insulator (FI) barrier. The ground state of such junction alternates between 0 and pi states when thickness of FI is increasing by a single atomic layer. We find that the mechanism of the 0-pi transition can be attributed to thickness-dependent phase shifts between the wave numbers of electrons and holes in FI. Based on these results, we show that a stable pi state can be realized in junctions based on high-T{c} superconductors with a La2BaCuO5 barrier.
authors.affiliation: Nanotechnology Research Institute (NRI), National Institute of Advanced Industrial Science and Technology (AIST), and JST-CREST, Tsukuba, Ibaraki, 305-8568, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Kawabata
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Asano
authors.forename: Yukio
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Golubov
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kashiwaya