Updated on 2024/09/27

写真a

 
MITSUDA AKIHIRO
 
Organization
Faculty of Science Department of Physics Associate Professor
Kyushu University Low Temperature Center (Concurrent)
School of Sciences Department of Physics(Concurrent)
Graduate School of Sciences Department of Physics(Concurrent)
Title
Associate Professor
Contact information
メールアドレス
Profile
a研究活動 希土類金属の4f電子の不安定性が引き起こす異常物性に注目して研究を行ってきた。特にEuとYb系の価数転移物質に着目し、前者では磁場誘起価数転移を、後者では圧力誘起強磁性転移を発見した。これらの現象は価数転移の解明に重要な情報を与えるものと考えられる。最近では、ナノスピン素子の圧力効果に関する研究も行なっている。 教育活動 理学部物理学科3年生向けの物性物理学Iを担当している。また物理学科3年生向けの物理学総合実験の取りまとめ役を担当している。大学院では磁性体物理学を担当している。

Degree

  • Doctor(Engineering)

Research History

  • 1999年4月〜2001年3月 日本学術振興会特別研究員(PD)(受入機関:東京大学物性研究所) 2001年4月〜2005年9月 富山大学理学部助手   

Research Interests・Research Keywords

  • Research theme: Pressure effects on nano spin device

    Keyword: pure spin current, GMR, Pressure effect

    Research period: 2016.10

  • Research theme: Study on valence fluctuating rare-earth compounds and alloys

    Keyword: Europium, Ytterbium, Valence fluctuation, Charge order, pressure

    Research period: 1994.4

Awards

  • 第2回日本金属学会・日本鉄鋼協会奨学賞

    1995.5   日本金属学会・日本鉄鋼協会  

Papers

  • Pressure-induced enhancement of spin-charge conversion efficiency in CoFeB/Pt bilayer Reviewed International journal

    #Riku Iimori, #Sora Obinata, @Akihiro Mitsuda, @Takashi Kimura

    Applied Physics Express   15   033003-1 - 033003-5   2022.2

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    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.35848/1882-0786/ac5501

  • Evolution of lattice coherence in the intermediate-valence heavy-fermion compound EuNi2P2 studied by point contact spectroscopy Reviewed International journal

    @Masanobu Shiga, @Isao Maruyama, #Kengo Okimura, #Takurou Harada, #Takuya Takahashi, @Akihiro Mitsuda, @Hirofumi Wada, @Yuji Inagaki, and @Tatsuya Kawae

    PHYSICAL REVIEW B   103 ( 4 )   L041113-1 - L041113-6   2021.1

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    Language:English   Publishing type:Research paper (scientific journal)  

    We performed a point contact spectroscopy study in an intermediate-valence heavy-fermion (HF) compound EuNi2P2. Above the Kondo temperature TK , the differential conductance spectra show a broad peak due to the Kondo resonance at the Eu site. Below TK , the broad peak splits into two peaks that can be reproduced by the summation of two Fano curves with the same parameters, indicating the emergence of the indirect hybridization
    gap in an Anderson lattice. With decreasing temperature, the separation between the two peaks increases and saturates at very low temperatures. The results reveal the evolution of the electronic structure in the HF state due to the development of the lattice coherence.

    DOI: 10.1103/PhysRevB.103.L041113

  • Pressure Effects on Magnetic and Transport Properties in CoFe-Based Spin Valve Reviewed

    @Akihiro Mitsuda, #Motoki Kaneda, #Kanta Matsutomo, @Takashi Kimura, @Hiromi Yuasa

    Materials Transactions   61 ( 8 )   1483 - 1486   2020.8

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    Language:English   Publishing type:Research paper (scientific journal)  

    We have studied the magnetoresistance of an enhanced-biased spin valve device under high pressure. The magnetoresistance decreases by 0.0014 up to 2 GPa with increasing pressure, which is inferred to be due to slight deviation from an antiparallel-spin configuration of the free and pinned layers. In the pressure range between 2 and 2.75 GPa, the exchange bias field generated in the pinned layer decreases and the coercivity of the free layers clearly increases by ∼5 Oe, which is likely to be related to less hydrostatic pressure.

    DOI: 10.2320/matertrans.MT-MN2019040

  • Observation of Kondo resonance in valence-ordered YbPd Reviewed International journal

    #Shiga Masanobu, #Okimura Kengo, #Takata Hiroki, @Mitsuda Akihiro, @Maruyama Isao, @Wada Hirofumi, @Inagaki Yuji, @Kawae Tatsuya

    Phys. Rev. B   100 ( 24 )   245117-1 - 245117-7   2019.12

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    Language:Japanese   Publishing type:Research paper (scientific journal)  

    We performed a point-contact spectroscopy study of intermediate valence compound YbPd, in which two Yb sites are ordered with the valence values of 3+ and 2.6+. Differential conductance spectra exhibit a dip structure at around zero bias with an asymmetric background, which can be reproduced by the summation of two Kondo resonances. Fitting with the Fano equation, the Kondo temperature of the 3+ site is estimated to be ∼30K, while that of the 2.6+ site is ∼800K. Additionally, the dip amplitude exhibits −lnT dependence below ∼25K and saturates at ∼1K. These results provide direct evidence for the screening of magnetic moments at the valence ordering sites owing to the Kondo effect.

    DOI: 10.1103/PhysRevB.100.245117

  • Neutron diffraction studies on valence ordering compound YbPd Reviewed International journal

    #Kohei Oyama, #Masaki Sugishima, #Kousuke Tanabe, @Akihiro Mitsuda, @Hirofumi Wada, @Kenji Ohoyama, @Takeshi Matsukawa, @Yukihiko Yoshida, @Akinori Hoshikawa, @Toru Ishigaki, @Kazuaki Iwasa

    journal of the physical society of japan   87 ( 11 )   114705-1 - 114705-6   2018.10

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    Language:English   Publishing type:Research paper (scientific journal)  

    The magnetic structure of YbPd was determined for a newly synthesized strain-free sample by neutron diffraction techniques. The sinusoidal magnetic structure characterized by an incommensurate wave vector k = (0.080 0 0.32) is observed in the magnetic-ordered phase between T3 = 1.9 K and T4 = 0.5 K, which is composed of the magneticmoment amplitude of 0.3 μB parallel to the a-axis in the tetragonal crystal-structure phase. The modulated magnetic structure is consistent with the previously proposed Yb-ion valence ordered structure appearing below T2 = 105 K, which consists of the periodic arrangement of magnetic and nonmagnetic Yb ions.

    DOI: 10.7566/JPSJ.87.114705

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Presentations

  • 非ThCr2Si2型の新規価数転移物質Eu2Pt6(Al1-xGax)15の磁場誘起価数転移 Invited

    光田暁弘

    強磁場オンライン研究会2021  2021.11 

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    Event date: 2021.11

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:オンライン   Country:Japan  

  • 圧力・磁場下におけるEu化合物の価数転移、価数秩序 Invited

    @光田暁弘

    日本物理学会第74回年次大会  2019.3 

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    Event date: 2019.3

    Language:Japanese   Presentation type:Symposium, workshop panel (public)  

    Venue:九州大学 伊都キャンパス   Country:Japan  

    最近、希土類化合物において価数揺らぎや価数転移が非従来型超伝導や非フェルミ液体的振舞を誘起することから注目が集まり、価数測定が盛んに行われるようになった。測定技術の進展により非常に僅かな価数変化も検知することができ、理論と実験の両面から研究が進んでいる。一方、我々は、より大きな価数変化によって興味深い振舞を示すEu化合物に注目をして研究を行ってきた。本講演では、最近の我々の研究から、圧力および磁場誘起価数転移と圧力誘起価数秩序について紹介する。

  • Inelastic x-ray scattering of valence fluctuating YbPd International conference

    Akihiro MITSUDA, Masaki Sugishima, Takumi Hasegawa, Satoshi Tsutsui, A. Q. R. Baron, Masayuki Udagawa, Hirofumi Wada

    The International Conferenece on Strongly Correlated Electron Systems 2013  2013.8 

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    Event date: 2013.8

    Language:English   Presentation type:Oral presentation (general)  

    Venue:The University of Tokyo, Hongo Campus   Country:Japan  

  • 価数転移物質 YbInCu4の 高温相の基底状態は何か? Invited

    光田暁弘

    日本物理学会  2002.9 

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    Presentation type:Oral presentation (invited, special)  

    Venue:中部大学   Country:Japan  

  • Experimental and Theoretical Evaluation for Pressure Effects on Spin Hall Effect in Pt International conference

    #Riku Iimori, #Sora Obinata, #Taishiro Yamazaki, @Akihiro Mitsuda, @Takashi Kimura

    Intermag 2023 Conference  2023.5 

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    Event date: 2023.5

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Sendai International Center   Country:Japan  

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MISC

  • YbPdにおける価数秩序構造を反映した磁気秩序

    #大山耕平, #田邉巧祐, @光田暁弘, @和田裕文

    九州大学低温センターだより   2020.3

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    Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)  

    Repository Public URL: http://hdl.handle.net/2324/4398966

  • What is Origin of the First Eu-Based Heavy Fermion?

    Akihiro MITSUDA

    Journal of Physical Society of Japan News and Comments   2013.8

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    Language:English   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)  

    Other Link: http://journals.jps.jp/doi/full/10.7566/JPSJNC.10.14

  • EuRh2Si2における圧力誘起価数転移

    光田暁弘, 浜野卓, 荒岡信隆, 矢山英樹, 和田裕文

    九州大学低温センターだより   2012.3

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    Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)  

  • Eu0.5Ca0.5Fe2As2におけるFeAsの圧力誘起超伝導とEu磁性の競合

    光田暁弘, 的場智広, 清家諭, 和田裕文, 石川 文洋, 山田 裕

    九州大学低温センターだより   2011.3

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    Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)  

  • 価数転移Yb化合物における圧力誘起弱強磁性

    光田暁弘

    高圧力の科学と技術   2005.1

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    Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)  

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Professional Memberships

  • 日本物理学会

  • 日本金属学会

  • 日本高圧力学会

Committee Memberships

  • 日本物理学会領域8   Steering committee member   Domestic

    2020.4 - 2021.3   

  • 日本物理学会九州支部   Organizer   Domestic

    2019.4 - 2020.3   

  • 日本物理学会九州支部   Organizer   Domestic

    2014.4 - 2015.3   

  • 日本物理学会九州支部   Organizer   Domestic

    2008.9 - 2009.8   

Academic Activities

  • Screening of academic papers

    Role(s): Peer review

    2022

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:1

  • Screening of academic papers

    Role(s): Peer review

    2021

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:2

  • Screening of academic papers

    Role(s): Peer review

    2020

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    Type:Peer review 

    Number of peer-reviewed articles in foreign language journals:1

  • 座長

    日本物理学会2019年秋季大会  ( Japan ) 2019.9

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    Type:Competition, symposium, etc. 

  • 実行委員

    日本物理学会第74回年次大会  ( Japan ) 2019.3

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    Type:Competition, symposium, etc. 

    Number of participants:5,000

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Research Projects

  • ユーロピウム化合物における新奇基底状態と価数不安定現象の相関の解明

    Grant number:23K03304  2023 - 2025

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Authorship:Principal investigator  Grant type:Scientific research funding

  • 希土類化合物が示す価数揺動・転移機構の共鳴X線分光複合計測とベイズ推定による解明

    Grant number:21H03739  2021 - 2024

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (B)

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    Authorship:Coinvestigator(s)  Grant type:Scientific research funding

  • 超高感度磁気物性評価システム

    2020

    研究環境整備(最先端設備)

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    Authorship:Coinvestigator(s)  Grant type:On-campus funds, funds, etc.

  • スピンナノ素子の圧力効果研究の確立

    Grant number:18K04875  2018 - 2022

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

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    Authorship:Principal investigator  Grant type:Scientific research funding

  • 静水圧力による純スピン流制御

    2017

    QRプログラム・わかばチャレンジ

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    Authorship:Principal investigator  Grant type:On-campus funds, funds, etc.

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Educational Activities

  • 理学部物理学科3年生向けの物性物理学Iを担当している。基幹教育科目として電磁気学基礎と熱力学基礎を担当している。

Class subject

  • 熱力学基礎

    2024.12 - 2025.2   Winter quarter

  • 電磁気学基礎

    2024.10 - 2024.12   Fall quarter

  • 物性物理学I

    2024.4 - 2024.9   First semester

  • 熱力学基礎

    2023.12 - 2024.2   Winter quarter

  • 磁性体物理学

    2023.10 - 2024.3   Second semester

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FD Participation

  • 2024.2   Role:Participation   Title:先導的人材育成フェローシップ量子分野会議と共催

    Organizer:Undergraduate school department

  • 2023.3   Role:Participation   Title:【物理学科FD】物理数学の教育と効果的な演習に向けて

    Organizer:Undergraduate school department

  • 2022.3   Role:Participation   Title:メンタルヘルス講習会

    Organizer:University-wide

  • 2022.3   Role:Participation   Title:ティーチング・フェロー制度の概要と講義での活用に向けて

    Organizer:Undergraduate school department

  • 2021.3   Role:Participation   Title:ハイブリッド講義の実践例と講義活性化

    Organizer:Undergraduate school department

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Visiting, concurrent, or part-time lecturers at other universities, institutions, etc.

  • 2020  兵庫県立大学・理学部  Classification:Intensive course  Domestic/International Classification:Japan 

    Semester, Day Time or Duration:前期

  • 2017  埼玉大学理学部・理工学研究科  Classification:Intensive course  Domestic/International Classification:Japan 

    Semester, Day Time or Duration:前期、9/4~5

  • 2014  新潟大学理学部  Classification:Intensive course  Domestic/International Classification:Japan 

    Semester, Day Time or Duration:前期

Other educational activity and Special note

  • 2023  Class Teacher  学部

  • 2015  Class Teacher  学部

  • 2014  Class Teacher  学部

  • 2013  Class Teacher  学部

  • 2012  Class Teacher  学部

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Outline of Social Contribution and International Cooperation activities

  • 高校生向けの体験入学の研究室見学を担当した。

Social Activities

  • 令和5年度リカレント教育・低温センター見学担当

    福岡県高等学校理科部会  2023.8

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

  • 体験物理学・公開講座において「磁石の物理」の授業を担当

    福岡県周辺の高校1,2年生、一般、高等専門学校生を対象  2023.3

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

  • 体験物理学・公開講座において研究室見学担当

    福岡県周辺の高校1,2年生、一般、高等専門学校生を対象  2022.3

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

  • 体験物理学・公開講座において実験担当

    福岡県周辺の高校1,2年生、一般、高等専門学校生を対象  2019.3

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

  • 体験物理学・公開講座において実験担当

    福岡県周辺の高校1,2年生、一般、高等専門学校生を対象  2018.3

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    Audience:Infants, Schoolchildren, Junior students, High school students

    Type:Seminar, workshop

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Travel Abroad

  • 2019.11

    Staying countory name 1:Viet Nam   Staying institution name 1:Duy Tan University

  • 2012.8

    Staying countory name 1:Czech Republic   Staying institution name 1:Charles University

  • 2012.7

    Staying countory name 1:Korea, Republic of   Staying institution name 1:Busan Exhibition Convention Center

  • 2010.6 - 2010.7

    Staying countory name 1:United States   Staying institution name 1:Santa Fe Convention Center

  • 2009.7

    Staying countory name 1:Germany   Staying institution name 1:Congress Center Karlsruhe

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