Single-Pass Three-Level Recording with FePt-L10 Granular Media in HAMR

Heat assisted magnetic recording with FePt-L10 granular media offers a unique opportunity for single-pass multi-level recording. In this paper, we present a micromagnetic simulation based modeling study to investigate the viability of the scheme, in particular, three-level recording. Because of the L10 ordering in the perpendicular direction, a FePt grain can be essentially viewed as a set of Fe atomic monolayers exchange coupled via the Pt monolayers in between throughout the grain height. Consequently, the exchange between a pair of Fe monolayers can be dynamic if the magnetization within a grain becomes non-uniform during the recording processes. It is shown that such dynamic exchange leads to domain wall trapping in the absence of head field, forming a "zero-moment" grain. Such mechanism enables single pass three level recording which will lead to a 58% linear density increase without increasing flux change density. The key to realizing this media characteristic property is to raise the order parameter of FePt-L10 granular medium to be above S > 0.9.

Saving the Past
Unlocking the Future

Cerabyte is pioneering a next-generation data storage technology designed to meet the rising global demand for ultra-durable, scalable, and sustainable long-term data preservation. At the core of Cerabyte's innovation is the use of ceramic nanolayers combined with laser-based writing and optical reading, offering a medium that is fundamentally more resilient and environmentally friendly than current storage technologies.

大規模ゲノム解析を支えるLustreファイルシステムの実運用と技術的課題

東京大学ヒトゲノム解析センターでは、がんや感染症などの疾患に対する新たな診断・治療法の開発を目指し、ゲノム研究とその情報インフラの構築を推進している。その研究活動を支える基盤として、スーパーコンピュータSHIROKANEを運用し、全国の生命科学研究者に広く計算資源を提供している。本講演では、SHIROKANEにおけるLustreファイルシステムを中心としたストレージ運用の現場から、データ移行、I/O負荷制御、冷却・湿度管理、ユーザ教育、テープ装置運用などに関する技術的課題と対応策を紹介する。

車載向けTMRセンサ最前線 ― HDD技術の他領域での進展 ―

モビリティの電動化・自動運転化は、サステイナブルな社会実現の重要テーマの一つとなっているが、実はTMR技術がその分野発展の一躍を担っている。TMR技術は、2004年HDDにて世界初の量産が始まったが、20年以上経過した現在においてもAI社会を支えるストレージ、HDDの再生ヘッドとしてなくてはならない存在である。従来の磁気センサであるHall・AMR・GMRに比べ高感度・高速応答・低消費電力・高信頼性などの特長から、現在において、TMRはストレージ以外の分野をも支える基幹技術となっている。本講演ではその最前線を紹介する。

The Future of Magnetic Tape

Magnetic tape is currently the lowest cost and greenest technology for storing large volumes of digital data. Historically, areal density scaling has been the main driver of the exponential decrease in cost, i.e. $/TB of capacity, of both tape and hard disk drives. Recently, HDD scaling has slowed significantly while tape continues to scale, resulting in a resurgence in interest in tape. The challenges of scaling magnetic recording systems will be discussed as well as the reasons for the current difference in scaling potential of HDD and tape technology. The Information Storage Industry Consortium (INSIC) Tape Technology Roadmap projects that tape areal density and capacity will continue to scale at historical rates for at least the next decade. The feasibility of these projections have been partially validated by a recent research tape areal density demonstration of 317 Gb/in2 on SrFe tape. The technologies that enabled this demonstration will be discussed along with the latest INSIC tape technology roadmap.

閉会挨拶

懇親会　（RIVER CAFE & DINING）