Select Language
アクセス数 Since 2009
今日 : 384
昨日 : 1073
今月 : 43644
総計 : 2541197
平均 : 646
Who am I ?
初貝 安弘 ORCID iD icon
筑波大学
筑波大学大学院
数理物質科学研究科
物理学専攻 教授
初貝写真
YasuhiroV.jpg
会議 & 研究会
グーグル検索:初貝
TAG index
ResercherID: Y.Hatsugai
Project
メインメニュー
"JSPS/EPSRC C2C meeting 2018", October 29-31 (2018), Tohoku Univ. Sendai
Y. Hatsugai
"Potential applications of topological phases"

Schedule for JSPS/EPSRC C2C meeting

29-31 October 2018

Seminar Room, Science Campus Hall- School of Engineering, Tohoku University,

6-6 Aza Aoba, Aoba-ku, Sendai, Japan



29th Oct. Open seminar        

(all day:2D electron-spin device related) 

Time

Speaker

University

Title

chair

9.30

Tetsuo Endoh

Tohoku Univ.

Welcome

mn

9.35

John Robertson

U. of Cambridge

Welcome

9.40

Junsaku Nitta

Tohoku Univ.

(tentative)Spin-orbit torques with Rashba spin-orbit coupling in epitaxial Pt/Co systems

10.10

Pierre Seneor

U. of Paris, Sud

Introducing 2D Materials in Magnetic Tunnel Junctions, from Graphene to h-BN

10.40

coffee

     

11.00

Makoto Kohda

Tohoku Univ.

Robustness of a persistent spin helix against

cubic Dresselhaus field in (001) and (110) oriented two-dimensional electron gases

si

11.30

Jack A-Webber

U. of Cambridge

Passivating and exploiting charge trapping in low-dimensional materials

12.00

Tomoya Ono

U. of Tsukuba

(tentative)DFT study on spin-dependent transport property of 2D materials

12.30

lunch

 

 

 

14.00

Marta Galbiati

U. of Paris, Sud

Efficient Spin Valves with Exfoliated MoS2 Multilayers

jr

14.30

Hiroshi Naganuma

Tohoku Univ.

One unit cell polarization sheet for 2D system

15.00

Ye Fan

U. of Cambridge

Production and potentials of 2D transition-metal-dichalcogenides (TMDC) in spintronics

15.30

coffee

 

 

 

16.00

All

 

Discussion

mk

19:00〜 Dinner   Kiraku-tei(Sendai)

30th Oct.  Open seminar 

(AM: 2D electromagnetic device interface related,  PM: 2D electron-spin device related)

9.00

John Robertson

U. of Cambridge

Semiconductor Band offsets

at

9.40

Kenji Shiraishi

Nagoya Univ.

ReRAM and iPCM by Charge Injection Mechanism

10.10

Al-Mahdawi Muftah

Tohoku Univ.

Modulating anisotropy of interfacial density of states in magnetic tunnel junctions

10.40

Mikihiko Oogane

Tohoku Univ.

Ferromagnetic ordered materials for spintronics

11.10

coffee

     

11.40

John Robertson

U. of Cambridge

Band design for a-GeSe selector devices for PRAM / RRAM

bd

12.00

Yasuhiro Hatsugai

U. of Tsukuba

Potential applications of topological phases

12.30

lunch

     

14.00

Victor Zatko

U. of Paris, Sud

Introducing CVD WS2 in Magnetic Tunnel Junctions 

sp

14.30

Ryo Mizuta

U. of Cambridge

CVD growth of 2D nanomaterials for spintronics

15.00

Kousuke Nagashio

The U. of Tokyo

Pinpoint pick up and bubble free transfer in 2D heterostructure fabrication

15.30

Bruno Dlubak

U. of Paris, Sud

Stabilizing 2D materials platforms towards discrete components

16.00

coffee

     

16.30

All

 

Discussion

kn



31th Oct.   

Over-all discussion

9.00

All

 

Discussion

mk

10.30

coffee

     

11:00-12.00

Testuo Endoh

Tohoku Univ.

Wrap up

Closing

te



前
[P]"Variety and universality of bulk-edge correspondence in topological phases: From solid state physics to transdisciplinary concepts"[ BEC2018X ], Dec. 9- 13 (2018), Myogadani, Tokyo
カテゴリートップ
国際会議、研究会、セミナー
次
[P]"Trends in Theory of Correlated Materials (TTCM 2018)”, Geneva (Switzerland), October 8-10 (2018)

モバイル機器でご覧の方
現在の時刻
今年もやります。まずは量子力学3(遠隔). 冬は 統計力学2 改め物性理論II (大学院「ベリー接続の理論とバルクエッジ対応」). 令和二年の新年あけましておめでとうございます。今年もあと67日!
最新ニュース
投稿者 : hatsugai 投稿日時: 2020-10-01 16:07:56 (172 ヒット)

Motivated by a historical example, the Dirac Hamiltonian as a square-root of the Klein-Gordon Hamiltonian, its lattice analogue has been discussed recently. Zero energy states are shared by the parent and its descendant. The story is more than that. Not necessarily zero energy but its high energy part can also share topological characters. We hereby propose a “square-root higher order topological insulator (square-root HOTI)” when its squared parent is HOTI. Based on the simple observation that square of the decorated honeycomb lattice is given by a decoupled sum of the Kagome and honeycomb lattices, we have demonstrate that the “corner states” of the breezing Kagome lattice with boundaries share topological characters with its descendant as the decorated honeycomb lattice. Have a look at our recent paper just published online, "Square-root higher-order topological insulator on a decorated honeycomb lattice" by Tomonari Mizoguchi, Yoshihito Kuno, and Yasuhiro Hatsugai, Phys. Rev. A 102, 033527 (2020), also arXiv:2004.03235.


投稿者 : hatsugai 投稿日時: 2020-09-17 11:42:01 (94 ヒット)

As for a topological characterization of a full Liouvillian (including jump term) for the non hermitian fractional quantum Hall states, we are proposing a pseudospin Chern number associated with the Niu-Thouless-Wu type twists in the doubled Hilbert space. Numerical demonstration of the proposal is explicitely given and its validity is discussed. Have a look at "Fate of fractional quantum Hall states in open quantum systems: Characterization of correlated topological states for the full Liouvillian" by Tsuneya Yoshida, Koji Kudo, Hosho Katsura, and Yasuhiro Hatsugai, Phys. Rev. Research 2, 033428 (2020) (open access).


投稿者 : hatsugai 投稿日時: 2020-09-17 11:06:17 (107 ヒット)

The Dirac cone is a typical singular energy dispersion in two dimensions that is a source of various non-trivial topological effects. When realized in real/synthetic materials, it is generically tilted and the equi-energy surface (curve) can be elliptic/hyperbolic (type I/II). The type III Dirac cone is a critical situation between the type I and II that potentially causes various non-trivial physics. As for realization of the type III Dirac cones, we are proposing a generic theoretical scheme without any fine tuning of material parameters . It may also help to synthesize in meta materials. The molecular orbital (MO) construction of the generic flat bands which we are also proposing plays a crutial role. Have a look at "Type-III Dirac Cones from Degenerate Directionally Flat Bands: Viewpoint from Molecular-Orbital Representation" by Tomonari Mizoguchi and Yasuhiro Hatsugai, J. Phys. Soc. Jpn. 89, 103704 (2020) Also arXiv:2007.14643.


投稿者 : hatsugai 投稿日時: 2020-08-16 14:53:28 (255 ヒット)

Adiabatic deformation of gapped systems is a conceptual basis of topological phases. It implies that topological invariants of the bulk described by the Berry connection work as topological order parameters of the phase. This is independent of the well-established symmetry breaking scenario of the phase characterization. Adiabatic heuristic argument for the fractional quantum Hall states is one of the oldest such trials that states the "FRACTIONAL" state is deformed to the “INTEGER”. Although it is intuitive and physically quite natural, there exist several difficulties. How the states with different degeneracy are deformed each other adiabatically? We have clarified the questions and demonstrated this adiabatic deformation on a torus in the paper "Adiabatic heuristic principle on a torus and generalized Streda formula" by Koji Kudo and Yasuhiro Hatsugai , Phys. Rev. B 102, 125108 (2020) (also arXiv:2004.00859) What is deformed continuously is a gap not the states ! This is also sufficient for the topological stability of the Chern number (of the degenerate multiplet) as a topological order parameter. Have a look at.


投稿者 : hatsugai 投稿日時: 2020-07-30 12:47:16 (239 ヒット)

Our article on non-hermitian band touching for strongly correlated systems has been published in PTEP (Progress of Theoretical and Experimental Physics), "Exceptional band touching for strongly correlated systems in equilibrium", by Tsuneya Yoshida, Robert Peters, Norio Kawakami, Yasuhiro Hatsugai. Focusing on the non-hermitian topological phenomena for the equilibrium Green function of correlated electrons, a compact review of the exceptonal band touching that is intrinsic for non-hermitian matrices is described as well. Have a look at.


    検索
    バルク・エッジ対応
    [0] バルクとエッジ
    [1] 集中講義
    [2] 原論文と解説
    [3] トポロジカル秩序とベリー接続:日本物理学会誌 「解説」 [JPS-HP] [pdf]
    [4] "Band gap, dangling bond and spin : a physicist's viewpoint" [pdf] [Web]
    トポロジカル相
    [0]昔の科研費
    科研費 1992年度:電子系スピン系におけるトポロジカル効果
    科研費 1994年度:物性論におけるトポロジーと幾何学的位相
    私の講演ファイルのいくつか
    [1] MIT, Boston (2003)
    [2] APS/JPS March Meeting (2004)
    [3] JPS Fall meeting, JAPAN (2004)
    [4] APS/JPS March meeting (2005)
    [5] JPS Fall meeting (2005):Entanglement
    [6] Superclean workshop, Nasu (2006)
    [7] MPIPKS, Dresden (2006)
    [8] KEK, Tsukuba (2007)
    [9] ETH, Zurich (2008)
    [10] ICREA, Sant Benet (2009)
    [11] JPS Meeting, Kumamoto (2009)
    [12]HMF19, Fukuoka (2010)
    [13] NTU, Singapore (2011)
    [14] ICTP, Trieste (2011)
    [15] Villa conf., Orland (2012)
    Web記事 カテゴリ一覧
    最新のエントリ
    Web記事 アーカイブ