Hideaki Kasai Department of Precision Science and Technology & Applied Physics Osaka University, Japan. 「コンピューティックスによる物質デザイン:複合相関と非平衡ダイナミクス」研究会 2012年3月16日(金)-3月17日(土) 東京大学本郷キャンパス Computational Materials Design –from basics to applications-. - PowerPoint PPT Presentation
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Hideaki Kasai Department of Precision Science and Technology & Applied Physics
Osaka University, Japan
「コンピューティックスによる物質デザイン:複合相関と非平衡ダイナミクス」研究会
2012年3月16日(金)-3月17日(土)
東京大学本郷キャンパス
Computational Materials Design –from basics to applications-
Spin Manipulation at Surfaces
1. Kondo Effect and Influence of the RKKY Interaction (Magnetic Dimer, Trimer)
2. Surface-Spintronics Device Magnetic Layer (Fe) on Non-Magnetic Substrate (Cu)
3. Catalyst for Oxygen Reduction Reaction Non-Magnetic Layer (Pt) on Magnetic Substrate (Fe)
Effect of Oxygen Vacancy
4. Resistance Random Access Memory
FAX: 06-6879-7859
AB INITIOCALCULATIONS
PHYSICAL MECHANISM
VIRTUAL TEST MATERIAL
Experiment
QUANTIZATION ofMECHANISM
FUNCTIONALVERIFICATION
ANALYSIS ofRESULTS
VERIFICATION
触媒デザイン 反応プロセスデザイン
Computational Materials Design® (CMD®)
Magnetic atoms on metal surface
Dr.Emi Minamitani 南谷英美
Real space observation of Kondo effect and RKKY interaction
Numerical Renormalization Group
Kondo effect & local spin interaction
Results, the separation dependence of the RKKY interaction
Spin-spin correlation function shows the oscillatory behavior due to the RKKY interaction in 2D. )( 12
221 RkJSS F
DRKKY
The strongest FM interaction at kFR12=0.9
The strongest AF interaction at kFR12=2.5
)(041.0),(3.0 eVeVU Parameters are set as
FM
AF
Nghiem Thi Minh Hoa
Magnetic adatoms on a metal surface:
- Kondo effect at a single adatom
+- RKKY, and direct interaction between
adatoms- Dimer-
Magnetic order?Frustration?
–Trimer- D3
The trimer problem
N. T. M. Hoa, W. A. Diño, and H. Kasai: J. Phys. Soc. Jpn. 81 (2012) 023706
t13
t12
R12
R13
Yosida-Kondo dominant regime
Magnetic frustration regime
Transition in the trimer system
N. T. M. Hoa, W. A. Diño, and H. Kasai: J. Phys. Soc. Jpn. 81 (2012) 023706.
Critical crossover
Dr. Tomoya Kishi (KOBELCO, Kobe Steel Co.)
博士論文
表面ナノ構造の磁性と伝導性に 関する理論的研究 (2005)
Magnetic and Transport Properties of Surface Nano-Structures
-2
-1.5
-1
-0.5
0
0.5
1
1.5
2
0 0.1 0.2 0.3 0.4 0.5Spin polarized GGA
Fe Thin Film on Cu(111)
EF
Majority spin
Minority spin
Surface state
Surface state
Surface Spintronics Device (PCT2004)
Spin Switch DeviceSpin Memory Device
Ballistic Spin Circuit (BSC)
① 膜厚が数原子層分の鉄原子薄膜、② 鉄原子薄膜を支える(111)面を上面にした銅薄膜③ 銅薄膜支持バッファー層基板、④ スピン伝導ドレイン端子、⑤ スピン伝導ソース端子、
Spin Flip
特願2003-179726号 ,
SURFACE-SPINTRONICS DEVICE
Patent No.: US 7,432,573 B2Date of Patent: Oct. 7, 2008