${\rm L}1_{0}$ Phase CoPt-TiO $_{2}$/FePt-TiO $_{2}$ Exchange Coupled Media With Small Switching Field

The effects of L1
₀
CoPt-TiO
₂
/FePt-TiO
₂
bilayer and (Co
_x
Fe
_100-x
)
₅₀
Pt
₅₀
-TiO
₂
(0 ¿ x ¿ 100 at.%) multilayer exchange coupled media on switching field and magnetization reversal mechanism were studied. Results showed that both bilayer and multilayer exchange coupled media with out-of-plane anisotropy in the hard and soft layers were effective to reduce the switching field of single layer FePt-TiO
₂
media. First order reversal curve (FORC) distribution indicated that switching field distribution in the bilayer and multilayer exchanged coupled media was significantly narrowed down compared to the single layer and magnetization reversal was ascribed to domain formation followed by domain wall motion.