Pd magnetism induced by indirect interlayer exchange coupling

Abstract

We show that very large paramagnetic moments are created in ultrathin Pd layers through indirect interlayer exchange coupling. Pd $L$-edge x-ray magnetic circular dichroism measurements show Pd moments in [Pd(2.5nm)/Cu(3nm)/Ni${}_{81}$Fe${}_{19}$(5nm)/Cu(3nm)]${}_{20}$ superlattices which are ferromagnetically aligned with the applied field and nearly 3% the size of Pd moments created in directly exchange coupled [Pd(2.5nm)/Ni${}_{81}$Fe${}_{19}$(5nm)]${}_{20}$ superlattices. The induced moment is two orders of magnitude larger than that expected from RKKY exchange acting on the bulk paramagnetic susceptibility of Pd.

5 pages, 3 figures, to appear in Phys. Rev. B