タイムリバーサルの対称性の破裂と,磁気二極の秩序のない自発的なホール効果
Yo Machida1, Satoru Nakatsuji, Shigeki Onoda
1[1] Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan [2] Present addresses: Department of Physics, Tokyo Institute of Technology, Meguro 152-8551, Japan (Y.M.); Department of Physics, University of Toyama, Toyama 930-8555, Japan (T.T.).
Nature
|December 17, 2009
まとめ
研究者らは,磁気特性が磁気秩序なしに時間逆転対称性を破るエキゾチックな状態であるキラルスピン液体の証拠を発見した. Pr(2) Ir(2) O(7) のこの発見は,異常なホール効果を用いて,これらのユニークなスピンテクスチャを調査しています.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- 量子マグネティズム 量子マグネティズムとは
- 挫折した磁気性
背景:
- スピン液体は,量子変動がスピン順序を阻害する,挫折した磁気系である.
- チラルのスピン液体は,磁気順序のない時逆対称性の破損を示す仮説的なクラスです.
- キラルスピン液体の実験的実現は,長年にわたる課題でした.
研究 の 目的:
- キラルスピン液体の存在を実験的に検証する.
- 挫折した磁石における時間逆行対称性の自発的なマクロスコーピック破壊を実証する.
- キラルなスピン液体の性質を示す物質を特定するために.
主な方法:
- 異常なホール効果を利用して,時間逆転対称性の破損を検出しました.
- 金属の挫折磁石 Pr(2)Ir(2)O(7) を調査しました.
- スピンの質感形成とスピンの氷のルール行動を推測するために磁気測定を行った.
主要な成果:
- Pr(2)Ir(2)O(7) で磁場ゼロで異常なホール効果の発生を観測した.
- このホール効果は,均一な磁化がない場合に発生し,自発的な対称性破裂を示しています.
- 磁気測定は,スピン氷の規則と一致するキラルなスピン質感の形成を示唆した.
結論:
- この発見は,キラル・スピン液体状態の出現の経験的証拠を提供する.
- 自発的なホール効果は,磁気二極の秩序ではなく,キラルなスピン質感に起因する.
- この研究は,物質のエキゾチックな量子状態を探求するための新しい道を開きます.
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