I am a postdoctoral researcher at the Institute for Solid State Physics, the University of Tokyo (Takashi Oka Group), 

conducting theoretical research on condensed matter physics. 



Contact →  akihiroozawa_issp.u-tokyo.ac.jp (  _→ @ )

・Institute for Solid State Physics (ISSP), the University of Tokyo, Takashi Oka Group

・ google scholar

Research keywords 


Electromagnetic response from the topological nature of electrons

Dirac/Weyl electron systems

Quantum transport phenomena

Spintronics phenomena,  such as electrically induced spin torque  for magnetic textures

Non-equilibrium quantum phenomena by a strong field


Research Grant


Grant-in-Aid for Research Activity Start-up

「Theory for voltage-induced magnon in magnetic Weyl semimetals」

 (Total) 2,470,000JPY

 (Direct)1,900,000JPY

 (Indirect) 570,000JPY


News

・2024/9/16-19 (New!)

My collaborators and I gave talks at the Physical Society of Japan's annual meeting in Hokkaido, Japan. 

・" Light-induced magnetization dynamics in topological semimetals"  Akihiro Ozawa, and Takashi Oka

・ "Analysis of current-induced effective magnetic field in compensated ferrimagnetic Weyl semimetal Ti2MnAl"  Tomonari Meguro,  Akihiro Ozawa, Koji Kobayashi, and Kentaro Nomura

・"Intrinsic spin Nernst effect in Dirac and Weyl semimetals" Taiki Matsushita, Akihiro Ozawa, Yasufumi Araki, Junji Fujimoto, and Masatoshi Sato

・2024/9/12 (New!)

A preprint about spin-orbit torque in ferrimagnetic Weyl semimetal from the topological mechanism is now available.   

 ・"Topological spin-orbit torque  in ferrimagnetic Weyl semimetal"

    Tomonari Meguro,  Akihiro Ozawa, Koji Kobayashi, Yasufumi Araki, and Kentaro Nomura, arXiv:2409.07106 (2024)

・2024/8/9 (New!)

We published theoretical work on a chirality-dependent gauge field in a magnetic Weyl semimetal Co3Sn2S2 tight-binding model, from  J. Phys. Soc. Jpn., and chosen as JPSJ editors' Choice!

 ・"Chiral gauge field in fully spin-polarized magnetic Weyl semimetal with magnetic domain walls "

      Akihiro Ozawa, Yasufumi Araki, and Kentaro Nomura J. Phys. Soc. Jpn 93, 094704 (2024)


・2024/6/13 

I gave an invited talk at Tokyo University of Science.

「磁性ワイル半金属における電磁応答の理論」

・2024/6/7-9 

I joined a workshop "New perspective in spintronics and quantum transport" and gave a poster presentation. 


・2024/3/7 

My collaborator T. Meguro (Kyushu univ)  and I gave talks at the American Physical Society, March meeting@Minneapolis, Minnesota. 

 ・"Theory of chiral gauge field in fully- spin-polarized magnetic Weyl semimetal Co3Sn2S2"

      Akihiro Ozawa, Yasufumi Araki, and Kentaro Nomura

・"Effective tight-binding model of compensated ferrimagnetic Weyl semimetal and analysis of spin-orbit torque"

      Tomonari Meguro, Akihiro Ozawa, Koji Kobayashi, and Kentaro Nomura

・2024/2/21 

I have attended a workshop, Iwate Spintronics School Winter 2024, Iwate, Japan. 

・2024/2/7 

 Our paper on the research of orbital magnetization and anomalous Hall effect in  Weyl semimetal with compensated ferrimagnetic ordering has been published.

"Effective Tight-Binding Model of Compensated Ferrimagnetic Weyl Semimetal with Spontaneous Orbital Magnetization" Tomonari Meguro, Akihiro Ozawa, Koji Kobayashi, and Kentaro Nomura  J. Phys. Soc. Jpn  93, 034703 (2024)

・2024/1/22 

 Our paper on the research of the spin Hall effect in magnetic Weyl semimetal has been published.

"Effective model analysis for intrinsic spin Hall effect with magnetism in the Stacked Kagome Weyl Semimetal  Co3Sn2S2"

Akihiro Ozawa, Koji Kobayashi, and Kentaro Nomura Phys. Rev. Applied 21, 014041(2024)

・2023/9/16  

My collaborators and I gave a talk at JPS annual meeting @Tohoku University,  Sendai.  I really enjoyed Sendai!


" 積層カゴメ磁性ワイル半金属におけるカイラルゲージ場", 小沢耀弘, 荒木康史, 野村健太郎, 講演番号19aA106-2

"補償フェリ磁性ワイル半金属の有効強束縛模型",  目黒智成, 小沢耀弘, 小林浩二, 野村健太郎, 講演番号 19aA106-4

"カゴメ格子化合物Coシャンダイトにおけるフロッケエンジニアリング" 奥村駿, 小沢耀弘, 岡隆史 講演番号 18pB200-3

・2023/8/31   

My research activity plan "Theory of voltage-induced magnon in magnetic Weyl semimetal" was chosen by "Grant-in-Aid for Research Activity Start-up". 

・2023/8/25   Paper for the intercorrelation between anomalous Hall effect and spin Hall effect in magnetic Weyl semimetal Co3Sn2S2 has been published. 

I have conducted the theoretical calculations using two-orbital model.  

We are so happy to hear  that this paper is selected as  Editors' Suggestion of Phys. Rev. B!

"Intercorrelated anomalous Hall and spin Hall effect in kagome-lattice  Co3Sn2S2-based shandite films"

Yong-Chang Lau, Junya Ikeda, Kohei Fujiwara, Akihiro Ozawa, Jiaxin Zheng, Takeshi Seki, Kentaro Nomura, Liang Du, Quansheng Wu, Atsushi Tsukazaki, and Koki Takanashi

Phys. Rev. B 108, 064429 (2023) (Editors' Suggestion)

・2023/5/25  Preprint for model analysis for intrinsic spin Hall effect in ferromagnetic Weyl semimetal is now available. This is a collaborative  work with Prof. Kentaro Nomura from Kyushu Univ. and Dr. Koji Kobayashi from Sophia Univ..

・2023/4/27   Preprint for model proposal of ferrimagnetic Weyl semimetal is now available.

This is a collaborative  work with Mr. Tomonari Muguro and Prof. Kentaro Nomura from Kyushu Univ. and Dr. Koji Kobayashi from Sophia Univ..

・2023/4/1  I have started a project researcher  at Institute for Solid State Physics, the University of Tokyo, Oka group.

・2023/3/31  I got a PhD degree from Tohoku University.[Title: "Theory for topological transport phenomena in magnetic Weyl semimetal" ]

・2023/3/31  Paper for  spin-charge conversion in magnetic Weyl semimetal Co3Sn2S2 with Prof. Seki et al., from Tohoku Univ, has been published. I have conducted the theoretical calculations using two-orbital model.

 

        "Enhancement of Spin-Charge Conversion Efficiency for Co3Sn2S2 across Transition from Paramagnetic to Ferromagnetic Phase"

                   Takeshi Seki, Yong-Chang Lau, Junya Ikeda, Kohei Fujiwara, Akihiro Ozawa,  Satoshi Iihama, Kentaro Nomura, Atsushi Tsukazaki,  Phys. Rev. Research 5, 013222 (2023)

・2023/3/22  

I gave a talk about spin-charge transport in magnetic Weyl semimetal in JPS conference @ online.  Dr. Koji Kobayashi, who is my collaborator, gave a talk about the related work as well. 


" 磁性ワイル半金属Co3Sn2S2有効模型におけるスピン/異常ホール効果の理論解析", 小沢耀弘, 小林浩二, 野村健太郎, 講演番号22aD1-12, オンライン


" カゴメ層状強磁性ワイル半金属Co3Sn2S2薄膜におけるホール伝導率の数値計算", 小林浩二, 小沢耀弘, 野村健太郎, 講演番号22aD1-13, オンライン

・2023/3/08  I gave a talk in March Meeting @Las Vegas, NV.


" Theory of spin/charge transport and magnetic orderings in stacked kagome-lattice Weyl semimetal",

 Akihiro Ozawa, Kentaro Nomura

・2023/2/28 Homepage restarted