0-pi Transitions in a Superconductor/Chiral Ferromagnet/Superconductor Junction induced by a Homogeneous Cycloidal Spiral

Thierry Champel (1, 2) , Tomas Löfwander (2, 3) , Matthias Eschrig (2, 4)

1 LPM2C - Laboratoire de physique et modélisation des milieux condensés
2 TFP - Institut für Theoretische Festkörperphysik
3 MC2 - Department of Microtechnology and Nanoscience
4 Fachbereich Physik [Konstanz]

We study the pi phase in a superconductor-ferromagnet-superconductor Josephson junction, with a ferromagnet showing a cycloidal spiral spin modulation with in-plane propagation vector. Our results reveal a high sensitivity of the junction to the spiral order and indicate the presence of 0-pi quantum phase transitions as function of the spiral wave vector. We find that the chiral magnetic order introduces chiral superconducting triplet pairs that strongly influence the physics in such Josephson junctions, with potential applications in nanoelectronics and spintronics.

Domaines: Supraconductivité [cond-mat.supr-con]

Thierry Champel, Tomas Löfwander, Matthias Eschrig. 0-pi Transitions in a Superconductor/Chiral Ferromagnet/Superconductor Junction induced by a Homogeneous Cycloidal Spiral. Physical Review Letters, 2008, 100, pp.077003. ⟨10.1103/PhysRevLett.100.077003⟩. ⟨hal-00259619⟩