Pd magnetism induced by indirect interlayer exchange coupling

TL;DR

This study demonstrates that ultrathin Pd layers can acquire large paramagnetic moments through indirect interlayer exchange coupling, significantly exceeding expectations based on bulk susceptibility.

Contribution

It reveals a novel mechanism for inducing large magnetic moments in Pd via indirect exchange coupling in superlattices, surpassing traditional RKKY predictions.

Findings

Pd moments are nearly 3% of directly coupled superlattices.

Induced moments are two orders of magnitude larger than RKKY predictions.

Large paramagnetic moments are created in ultrathin Pd layers through indirect 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.