Hierarchical Recording Architecture for Three-Dimensional Magnetic Recording

TL;DR

This paper proposes a hierarchical layered heat-assisted writing architecture for 3D magnetic recording, validated through micromagnetic simulations, demonstrating improved signal-to-noise ratio and potential for multi-layer scaling.

Contribution

It introduces a novel hierarchical recording architecture with layered heat-assisted writing and validates it via simulations, advancing multi-layer 3D magnetic recording technology.

Findings

Identified optimal head-to-head distance for maximum SNR

Achieved appreciable switching probability and medium SNR in simulations

Demonstrated potential for scaling to more recording layers

Abstract

Three-dimensional magnetic recording (3DMR) is a highly promising approach to achieving ultra-large data storage capacity in hard disk drives. One of the greatest challenges for 3DMR lies in performing sequential and correct writing of bits into the multi-layer recording medium. In this work, we have proposed a hierarchical recording architecture based on layered heat-assisted writing with a multi-head array. The feasibility of the architecture is validated in a dual-layer 3DMR system with FePt-based thin films via micromagnetic simulation. Our results reveal the magnetization reversal mechanism of the grains, ultimately attaining appreciable switching probability and medium signal-to-noise ratio (SNR) for each layer. In particular, an optimal head-to-head distance is identified as the one that maximizes the medium SNR. Optimizing the system's noise resistance will improve the overall SNR and allow for a smaller optimal head-to-head distance, which can pave the way for scaling 3DMR to more recording layers.