Overcoming the Trilemma Issues of Ultrahigh Density Perpendicular Magnetic Recording Media by L1₀-Fe(Co)Pt Materials

Abstract

L1 0 -ordered FePt and CoPt (collectively called L1 0 -Fe(Co)Pt in this review) have become potential materials for future ultrahigh density perpendicular magnetic recording (PMR) media due to their high magnetocrystalline anisotropy, rendering small grains with high thermal stability. However, PMR media using such high anisotropy faces the well-known trilemma issues among thermal stability, signal-to-noise ratio (SNR), and writability. This paper will provide an overview of the impact of L1 0 -Fe(Co)Pt on overcoming the superparamagnetic limit and balancing the trilemma issues for ultrahigh density PMR media. Here the research and development of L1 0 -Fe(Co)Pt materials will be presented, from the perspectives of enhancing thermal stability, SNR and writability. Furthermore, we will provide some combined approaches to tackle the challenges in balancing the trilemma issues, focusing on materials engineering. SPIN 2015.05. Downloaded from www.worldscientific.com by MONASH UNIVERSITY on 08/25/15. For personal use only. Overcoming the Trilemma Issues of Ultrahigh Density PMR 1530002-3 SPIN 2015.05. Downloaded from www.worldscientific.com by MONASH UNIVERSITY on 08/25/15. For personal use only.

Influence of the Finite-size Effects on the Curie Temperature of L10-FePt

“…Among many possible candidates for a HAMR recording layer material, Iron Platinum in L1 0 -phase (L1 0 -FePt) has been regarded as an excellent choice [5]. L1 0 -FePt has been widely studied for application in HAMR in which L1 0 -FePt can function either as a single layer or as part of a composite multi-layer recording medium [6][7][8][9][10][11]. FePt undergoes a transition at around 300 o C from the bulk alloy A1 phase with a disordered, randomly distributed face-center cubic (fcc) crystal structure to a chemically ordered face-center tetragonal (fct) crystal structure in the L1 0 phase [12].…”

Influence of finite-size effects on the Curie temperature ofL10−FePt

“…Among many possible candidates for a HAMR recording layer material, iron platinum in the L1 0 phase (L1 0 -FePt) has been regarded as an excellent choice [5]. L1 0 -FePt has been widely studied for application in HAMR in which L1 0 -FePt can function either as a single layer or as part of a composite multilayer recording medium [6][7][8][9][10][11]. FePt undergoes a transition at around 300 • C from the bulk alloy A1 phase with a disordered, randomly distributed face-centered-cubic (fcc) crystal structure to a chemically ordered face-centeredtetragonal (fct) crystal structure in the L1 0 phase [12].…”