Tunability of the interlayer exchange coupling

摘要

The effect of the interlayer exchange coupling on the ordering temperature of ultrathin magnetic layers has been explored for two systems: Ho/Y and Fe/V superlattices. In both cases, the exchange coupling can be modified and eventually removed by the introduction of hydrogen into the mediating non-magnetic spacer layer. In case of Ho/Y we observed a drastic drop of the Ho Neel temperature from 105 K for coupled Ho blocks of 10 monolayer thickness to 65 K for isolated or uncoupled Ho blocks. In Fe/V superlattices, the incorporation of hydrogen changes the strength and sign of the exchange coupling constant. Again, we observed that the ordering temperature clearly depends on the strength of the exchange coupling in both the antiferromagnetically and the ferromagnetically coupled range of the phase diagram. [References: 20]