Details of a Researcher - Nozaki, Yukio

Nozaki, Yukio

写真a

Affiliation: Faculty of Science and Technology, Department of Physics (Yagami)

Position: Professor

Related Websites

Page Top ▲

Career 【 Display / hide 】

1998.04

-

2006.07

Assistant Professor, ISEE, Kyushu University, システム情報科学研究院, 助手
2006.08

-

2010.03

Assoc. Professor, ISEE, Kyushu University, システム情報科学研究院, 准教授
2010.04

-

2016.03

Assoc. Professor, Dept. of Physics, Keio University, 理工学部物理学科, 准教授
2016.04

-

2017.03

東京大学, 物性研究所, 客員教授
2016.04

-

Present

Assoc. Professor, Dept. of Physics, Keio University, 理工学部物理学科, 教授

Page Top ▲

Academic Background 【 Display / hide 】

1993.03

Keio University, Faculty of Science and Engineering, Department of Physics

University, Graduated
1995.03

Keio University, Graduate School, Division of Science and Engineering, Department of Physics

Graduate School, Completed, Master's course
1998.03

Keio University, Graduate School, Division of Science and Engineering, Department of Physics

Graduate School, Completed, Doctoral course

Page Top ▲

Academic Degrees 【 Display / hide 】

Ph, D, Keio University, Coursework, 1998.03

Page Top ▲

Research Areas 【 Display / hide 】

Natural Science / Magnetism, superconductivity and strongly correlated systems (Physical Properties II)

Page Top ▲

Research Keywords 【 Display / hide 】

Spin dynamics
Spintronics
Spin Mechatronics
Magnetism
Magnetic device

display all >>

Page Top ▲

Research Themes 【 Display / hide 】

非線形スピンダイナミクスの温度依存性に関する研究,

2016.04

-

Present
巨視的回転と微視的スピン角運動量の双方向変換,

2015.04

-

Present
チューナブル回転磁場の生成と非線形スピンダイナミクス励起に関する研究,

2015.04

-

Present
非平衡状態の非線形ダイナミクスに関する研究,

2014.04

-

Present
スピンダイナミクス由来のスピン流によるスピン移行トルクの測定,

2014.04

-

Present

display all >>

Page Top ▲

Papers 【 Display / hide 】

Highly accurate evaluation of spin-torque efficiency by measuring in-plane angular dependence of spin-torque ferromagnetic resonance

Horaguchi T., Matsuo M., Nozaki Y.

Journal of Magnetism and Magnetic Materials (Journal of Magnetism and Magnetic Materials) 505 2020.07

ISSN 03048853

　View Summary

© 2020 Spin-torque ferromagnetic resonance (ST-FMR) is a powerful tool to evaluate spin-torque efficiency (ξFMR), the efficiency of current-induced torque in metallic bilayers consisting of ferromagnetic and nonmagnetic materials. In general, ξFMR can be evaluated from the amplitude ratio between symmetric and anti-symmetric components of the ST-FMR spectrum. However, the ratio is also affected by an unnecessary magnetic field owing to the asymmetric alternating current flow used to excite the ST-FMR. In this article, we demonstrate that ξFMR can be precisely evaluated from the full-angular dependence of the ST-FMR spectrum even though the distribution of alternating current flow is highly asymmetric.
- Access to Document (DOI)
Observation of Gyromagnetic Spin Wave Resonance in NiFe Films

Kurimune Y., Matsuo M., Nozaki Y.

Physical Review Letters (Physical Review Letters) 124 ( 21 ) 2020.05

ISSN 00319007

　View Summary

© 2020 American Physical Society. This Letter demonstrates spin wave resonance (SWR) owing to the gyromagnetic effect by propagating a Rayleigh-type surface acoustic wave (R-SAW) through ferromagnetic thin films. The SWR amplitude in a NiFe film shows a higher-order frequency variation than in a magnetoelastic Ni film. This frequency dependence is well understood in terms of the presence of a gyromagnetic field attributable to the local lattice rotation in the R-SAW. From the frequency dependence of the SWR amplitude, the gyromagnetic SWR could be separated from another SWR caused by a magnetoelastic effect of the ferromagnet.
- Access to Document (DOI)
Highly nonreciprocal spin waves excited by magnetoelastic coupling in a ni / si bilayer

Tateno S., Nozaki Y., Nozaki Y.

Physical Review Applied (Physical Review Applied) 13 ( 1 ) 2020.03

　View Summary

© 2020 American Physical Society. We demonstrate a largely enhanced nonreciprocal propagation of spin waves (SWs) magnetoelastically excited in Ni/Si bilayer films. The nonreciprocity is attributed to the shear component of the strain tensor, which can be enlarged by increasing the thickness of the Si layer. By evaporating a 400-nm-thick Si layer on a Ni film, we enhanced the nonreciprocal ratio by up to 1200%. This finding paves the way for rectification of SWs in magnonic devices.
- Access to Document (DOI)
Spin waves parametrically excited via three-magnon scattering in narrow NiFe strips

Okano G., Nozaki Y.

Physical Review B (Physical Review B) 100 ( 10 ) 2019.09

ISSN 24699950

　View Summary

© 2019 American Physical Society. Three-magnon scattering can be used to evaluate the lowest frequency of the magnon band in a ferromagnet. Both the ferromagnetic-resonant (FMR) frequency fFMR and the lowest frequency of the magnon band fmin in narrow-shaped NiFe strips were electrically measured using the anisotropic-magnetoresistance effect. The comparison with a micromagnetic simulation shows that fmin of the magnon band can be controlled independent of fFMR by varying the width w and thickness t of the NiFe strip while maintaining a constant t/w ratio. In addition, we found that the frequency difference, fFMR-fmin, can be greatly increased in thicker NiFe strips. Our results show that narrow-shaped ferromagnets allow us to tune the magnon-band structures by varying their w and t. This ability is important for designing magnon circuits in integrated magnonic devices and for improving the quantitative study on the Bose-Einstein condensation of magnons.
- Access to Document (DOI)
Nonreciprocal Spin Current Generation in Surface-Oxidized Copper Films

Okano G., Matsuo M., Ohnuma Y., Maekawa S., Nozaki Y.

Physical Review Letters (Physical Review Letters) 122 ( 21 ) 2019.05

ISSN 00319007

　View Summary

© 2019 American Physical Society. We experimentally demonstrate the nonreciprocal generation of spin current (Js) in a surface-oxidized copper film. The efficiency of conversion is at least 320 times larger than the inverse conversion. This nonreciprocity is due to a novel type of Js generation, which relies on the transfer of angular momentum from the velocity field of free electrons. A gradient in the electrical mobility in the film produces vorticity in the in-plane drift velocity of the free electrons. The inverse process can hardly occur when Js is collinear with the gradient in the electrical mobility.
- Access to Document (DOI)

display all >>

Page Top ▲

Papers, etc., Registered in KOARA 【 Display / hide 】

Study on efficient generation of spin current using macroscopic angular momentum

Nozaki, Yukio

科学研究費補助金研究成果報告書 2020
Research on dynamical process of spinwave-assisted magnetization reversal and observation of spinwaves excited along thickness direction

Nozaki, Yukio

科学研究費補助金研究成果報告書 2016
Low power consuming magnetization reversal using electric field coupled spin injector

Nozaki, Yukio

科学研究費補助金研究成果報告書 2014
Research on 3 dimensional magnetic recording for high-capacity and low power consuming storage technologies

Nozaki, Yukio

科学研究費補助金研究成果報告書 2013
Microwave-assisted magnetization reversal of perpendicularly magnetized nanoscale magnetic dot and its applications to nonvolatile memories

Nozaki, Yukio

科学研究費補助金研究成果報告書 2010

Page Top ▲

Presentations 【 Display / hide 】

Giant nonreciprocity in spinwave propagation magnetoelastically excited in Ni/Si bilayer films

S. Tateno and Y. Nozaki

Intermag 2020,

2020.05
,
Poster presentation
Electrical control of parametric magnon exitation via spin current generated using naturally-oxidized copper film

G. Okano and Y. Nozaki

Intermag 2020,

2020.05
,
Poster presentation
NiFe/Dy 二層膜における実効的ギルバート定数の温度依存性

山野井一人, 榊原有理, 能崎幸雄

日本物理学会第75回年次大会,

2020.03
,
Oral presentation (general)
スピン渦度結合によりPtで励起される交流スピン流の温度依存性

松尾拓海, 山野井一人, 能崎幸雄

応用物理学会春季学術講演会,

2020.03
,
Poster presentation
非磁性金属/磁性金属の二層膜における一方向性スピンホール磁気抵抗効果の温度依存性

深見周平, 岡野元基, 山野井一人, 能崎幸雄

応用物理学会春季学術講演会,

2020.03
,
Poster presentation

display all >>

Page Top ▲

Research Projects of Competitive Funds, etc. 【 Display / hide 】

Chimera Quasiparticles: Physics

2024.04

-

2029.03

学術変革領域研究(A), Principal investigator
Study on the microscopic mechanism of non-adiabatic gyromagnetic effect through crystallographic texture control and manifestation of giant spin torque

2024.04

-

2027.03

基盤研究(A), Principal investigator
Study on multi-scale angular momentum conversion and generation of mechanical rotation from electron spin

2021.04

-

2024.03

MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (A) , Principal investigator
ナノ構造制御と計算科学を融合した傾斜材料開発とスピンデバイス応用

2019.10

-

2025.03

JST, CREST, Research grant, Principal investigator
音波を用いたスピン流の高効率生成と伝導制御に関する研究

2018.04

-

2021.03

MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (A) , Principal investigator

display all >>

Page Top ▲

Intellectual Property Rights, etc. 【 Display / hide 】

スピントロニクスデバイス、磁気メモリ及び電子機器

Date applied： PCT/JP2019/034831 2019.09

Patent, Single
スピントロニクスデバイス、磁気メモリ及び電子機器

Date applied： 2018-165900 2018.09

Patent, Single
静磁気結合を利用した磁性ランダムアクセスメモリセル

Date issued：特許 2003-408344 2011.06

Patent, Joint
磁性多層膜ドットを用いた高周波デバイス

Date issued：特許第4189502

Patent, Joint
磁気メモリ装置及びその書き込み方法

Date announced：特許公開2007－242092

Patent

display all >>

Page Top ▲

Awards 【 Display / hide 】

SRC論文賞2009

NOZAKI Yukio, 2010.06, Microwave-assisted magnetization reversal in a Co/Pd multilayer with perpendicular magnetic anisotropy Applied Physics Letters, Vol. 95, No. 8, Art. No. 082505 (August, 2009).

Type of Award： Award from publisher, newspaper, foundation, etc.
日本磁気学会論文賞

能崎幸雄, 立石健太郎, 白石壮馬, 松山公秀, 2009.09, サブミクロン幅NiFe薄膜パターンのマイクロ波アシスト磁化反転 Journal of Magnetic Society of Japan, Vol. 33, No. 3, pp.208 – 211 (2009)

Type of Award： Award from Japanese society, conference, symposium, etc.
Storage Research Consortium(SRC) 2009年度論文賞

2009.06
日本磁気学会論文賞

2008.09
第1回全学教育優秀授業賞（九州大学）

NOZAKI Yukio, 2007.09

Type of Award： Other