FePt-based exchange-coupled composites consisting of a magnetically hard L10-FePt phase exchange- coupled with a soft ferromagnetic material are promising candidates for future ultra-high density (>1Tbit/in2) perpendicular magnetic recording media, also being of interest for other applications includ-ing spin torque oscillators and micro-electro-mechanical systems, among others. In this paper, the effect of the thickness of a soft Co layer (3 < thCo < 20 nm) on the magnetic behavior of ledge-type fcc(100)-Co/L10(001)-FePt composites deposited on an MgO (100) substrate is systematically studied by combining morpho-structural analyses and angular magnetization measurements. Starting from a film consisting of isolated L10(001)-FePt islands, the ledge-type structure was obtained by depositing a Co layer that either covered the FePt islands or filled-up the inter-island region, gradually forming a continuous layer with increasing Co thickness. A perpendicular anisotropy was maintained up to thCo9.5 nm and a significant reduction in the coercivity (about 50% for thCo =3nm) with the increase inthCo was observed, indicating that, by coupling hard FePt and soft Co phases in a ledge-type configura- tion, the writability can be greatly improved. Recoil loops' measurements confirmed the exchange- coupled behavior, reinforcing a potential interest in these systems for future magnetic recording media.

Ledge-type Co/L10-FePt exchange-coupled composites

E Agostinelli;S Laureti;D Peddis;A M Testa;G Varvaro
2016

Abstract

FePt-based exchange-coupled composites consisting of a magnetically hard L10-FePt phase exchange- coupled with a soft ferromagnetic material are promising candidates for future ultra-high density (>1Tbit/in2) perpendicular magnetic recording media, also being of interest for other applications includ-ing spin torque oscillators and micro-electro-mechanical systems, among others. In this paper, the effect of the thickness of a soft Co layer (3 < thCo < 20 nm) on the magnetic behavior of ledge-type fcc(100)-Co/L10(001)-FePt composites deposited on an MgO (100) substrate is systematically studied by combining morpho-structural analyses and angular magnetization measurements. Starting from a film consisting of isolated L10(001)-FePt islands, the ledge-type structure was obtained by depositing a Co layer that either covered the FePt islands or filled-up the inter-island region, gradually forming a continuous layer with increasing Co thickness. A perpendicular anisotropy was maintained up to thCo9.5 nm and a significant reduction in the coercivity (about 50% for thCo =3nm) with the increase inthCo was observed, indicating that, by coupling hard FePt and soft Co phases in a ledge-type configura- tion, the writability can be greatly improved. Recoil loops' measurements confirmed the exchange- coupled behavior, reinforcing a potential interest in these systems for future magnetic recording media.
2016
Istituto di Struttura della Materia - ISM - Sede Roma Tor Vergata
FePt composites; magnetic recording media
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.14243/317426
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact