Giant spin-valve effect in Al/Y3Fe5O12 heterostructures

Superconducting phase transition in the aluminium stripes fabricated on yttrium-iron garnet and on oxidized silicon substrates is studied. Reduction of critical temperature, widening of superconducting transition depending upon the mutual current and magnetization orientations as well as on current strength are observed in aluminium on garnet comparing with aluminium on silicon. The proximity and triplet proximity effects, Andreev reflection, exchange interaction, spin-orbit coupling and self YIG magnetic field impacts on the observed effects are discussed. We show that only accounting for the spin-orbit coupling and self-magnetic field of YIG is allowed to explain the observed phenomenon of asymmetric change in the transition under the variation of the current and magnetization alignment. Based on the obtained results, we suggest a new geometry of spin-valve with hundreds percent variation of the resistance controlled by the current.