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Research

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HDD :;±<*CDkE4!The first major application

of nanotechnology

Peter Grünberg

(Germany)!

Albert Fert

(France)!

Giant Magnetoresistance (GMR)

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Nobel week, December 2007!

ノーベル賞講演にて　12月8日

スウェーデンロイヤルアカデミーによるレセプションにて　12月7日

授賞式にて 12月10日

晩餐会にて 12月10日

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C1b structure!

XYZ

L21 structure!

X2YZ (NiMnSb etc.)

(Co2MnSi, Co2MnGe etc.)

half-Heusler full-Heusler

Co2MnSi (CMS)

Half-metallic energy gap : 400 – 600 meV

Highly ordered L21-structure is

easily obtained.

High Tc (~ 985K)

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(Seagate)!

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(HGST)!

Target

2 Tbit/in2!

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(NHK)!3d Ferro CPP-GMR

(Toshiba)!

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(Fujitsu)!

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! The highest MR ratio (28.8%@RT) is the

best record in all of the reports to date.

Fully-epitaxial growth in CMS/Ag/CMS

Co2MnSi/Ag/Co2MnSi fully-epitaxial CPP-GMR device!

Iwase et al., Appl. Phys. Express, 2, 063003 (2009).

書き込み

読み出し

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Current-induced domain wall motion

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by spin polarized current in a permalloy

nanowire without external magnetic field

(A. Yamaguchi et al., PRL 92 (2004) 077205.)

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Current-induced vortex core motion

(S. Kasai et al., PRL 101 (2008) 237203.)

Time-resolved M-TXM observation of

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Electrical detection of giant spin

Hall effect at room temperature

T. Seki et al., Nature Materials, 7 (2008) 125.

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