Select Language
アクセス数 Since 2009
今日 : 87
昨日 : 211
今月 : 6000
総計 : 1492597
平均 : 526
Who am I ?
初貝 安弘
物理学専攻 教授
会議 & 研究会
TAG index
ResercherID: Y. Hatsugai
投稿者 : hatsugai 投稿日時: 2015-06-18 11:46:16 (676 ヒット)

Our paper "Topological Order Parameters of the Spin-1/2 Dimerized Heisenberg Ladder in Magnetic Field" is published in Phys. Rev.B . [arXiv:1412.7901] . Fractinal quantization of the Berry phase as pi/4 is quite useful for  characterization of some spin ladder with magnetic field.

投稿者 : hatsugai 投稿日時: 2015-06-07 05:55:51 (670 ヒット)


投稿者 : hatsugai 投稿日時: 2015-03-25 05:33:11 (631 ヒット)

チャーン数に関する私たちの論文 "Chern Numbers in Discretized Brillouin Zone: Efficient Method of Computing (Spin) Hall Conductances" ( T. Fukui, Y. Hatsugai, H. Suzuki ) が第20回(2015年)日本物理学会論文賞に選ばれました。ありがとうございました。

投稿者 : hatsugai 投稿日時: 2015-03-09 11:42:24 (698 ヒット)

The paper "Disentangled topological numbers by a purification of entangled mixed states for non-interacting fermion systems" by Takahiro Fukui and YH is now published in J. Phys. Soc. Jpn. 74, 1674 (2015), also on the net arXiv:1501.07031

投稿者 : hatsugai 投稿日時: 2015-02-25 10:54:05 (921 ヒット)

Flat bands in Weaire-Thorpe model and silicene is discussed and the paper is now published in New J. Phys. as a special issue article for silicene.. Electronic structure of silicene is algebraically described which is qualitatively consistent with the first principle results. Silicene is not a simple generalization of graphene but is featured by the multi-orbital character. Generic arguments for the flat band we have proposed before is nicely applied. [arXiv:1410.7885]

投稿者 : hatsugai 投稿日時: 2015-02-19 00:54:08 (963 ヒット)

Massive/massless Dirac cones with/without tilting for 2D semiconductors are described and now the paper has been published in Phys. Rev.B. 4D notations are used for compact derivations of the Landau levels of Dirac cones, extended chiral symmetry and generalized Aharonov-Casher type shifted zero modes. [arXiv:1410.6250] This is a kind of general description of the narrow gap semiconductor as the gapped Dirac cones with tilting. I am sure it can be useful.

投稿者 : hatsugai 投稿日時: 2014-08-19 13:29:55 (712 ヒット)

Takahiro Fukui and I have put a new paper "Entanglement Chern number for an extensive partition of a topological ground state" on the net. It can be a useful tool for several topological phases where conventional Chern numbers are trivial due to some symmetrical constraints. [arXiv]

投稿者 : hatsugai 投稿日時: 2014-08-06 13:13:14 (978 ヒット)

Our recent paper with Toshikaze Kariyado is accepted for publication in Phys. Rev. B where the bulk-edge correspondence is discussed with the Berry connections and adiabatic continuation. As an example, lattice Dirac fermions with 1/4 filling are described with several types of edges where quantized Berry phases in unit of pi/2 is useful. Have a look at [arXiv:1404.4451]

投稿者 : hatsugai 投稿日時: 2014-07-08 18:35:51 (904 ヒット)

Now our paper is published in Phys. Rev. B. It is also on the net arXiv:1403.1648, "Polarization as a topological quantum number in graphene" with Hideo Aok. In the article, one more topological invariant for the Hofstadter problem and graphene is described. Have a look at.

投稿者 : hatsugai 投稿日時: 2014-05-22 13:41:08 (753 ヒット)

第35回 数理の翼 夏季セミナー で8月に話をします。皆さんmotivationが高そうなので楽しみにしています。[概要]

« 1 2 (3) 4 5 6 »
今年もやります。まずは量子力学3. 冬は 統計力学2. 平成29年の新年あけましておめでとうございます。今年もあと99日!
投稿者 : hatsugai 投稿日時: 2017-08-17 17:01:30 (201 ヒット)

初貝研究室では今回助教2名を公募いたします(公募締め切り2017年9月15日)。委細は [助教公募] をご確認ください。適任者のご推薦、ご応募の方よろしくお願いいたします。

投稿者 : hatsugai 投稿日時: 2017-08-17 17:00:09 (86 ヒット)

We are organizing a Japan-Swiss workshop TTCM2017 at EPOCHAL Tsukuba, Sep.10-13 (2017). Limited number of posters will be still accepted.

投稿者 : hatsugai 投稿日時: 2017-08-03 13:38:17 (142 ヒット)

A numerical scheme to calculate the many body Chern number for a ground state multiplet is formulated and explicitly given for projected bands of any lattice. We demonstrate its validity for lattice analogue of the nu=1/3 and 1/2 states. The string gauge to realize the minimum flux compatible with the periodicity of the unit cell is also presented. [arXiv:1707.06722]. The paper is published in JPSJ lett.

投稿者 : hatsugai 投稿日時: 2017-04-21 19:57:50 (228 ヒット)

数理科学5 月号(2017年)に「物理学における線形代数:量子力学での展開」として小話を3つ書きました。1.量子もつれ, 2.平坦バンド, 3. ベリー接続としての単磁極.興味のある方はご覧ください.「物理学と数学のつながり」数理科学 5月号

    [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]
    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
    [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
    Web記事 アーカイブ