Events

Division of Low Temperature and Superconductivity Seminar

Manifestation of New Interference Effects in Superconductor/Ferromagnet Spin Valve

Prof. I. A. Garifullin

Zavoisky Physical-Technical Institute, Kazan Scientific Center of Russian Academy of Sciences, Kazan, Russia

Superconductor/ferromagnet (S/F) spin valve effect theories based on the S/F proximity phenomenon assume that the superconducting transition temperature Tc of F1/F2/S or F1/S/F2 trilayers for parallel magnetizations of the F1- and F2-layers (T_c^P) are smaller than for the antiparallel orientations (T_c^AP). Here, we report for CoO_x/Fe1/Cu/Fe2/In multilayered systems with varying Fe2-layer thickness the sign-changing oscillating behavior of the spin valve effect ΔTc =T_c^AP-T_c^P. Our measurements revealed the full direct spin valve effect with T_c^AP>T_c^P for Fe2-layer thickness d_Fe2<1nm and="" the="" full="" inverse="" t="" sub="">c^APc^P) spin valve effect for d_Fe2 >1nm. Interference of Cooper pair wave functions reflected from both surfaces of the Fe2-layer appear as the most probable reason for the observed behavior of ΔTc.