スピン軌道結合金属Cd2Re2O7における対数分解電子ネマティック・フェーズトランジション
J W Harter1,2, Z Y Zhao3,4, J-Q Yan3,5
1Department of Physics, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|April 22, 2017
まとめ
研究者らは金属のピロクロールCd2Re2O7に新しい多極性ネマティック相を発見した. この相は回転対称性を破り,強力なスピン軌道結合により空間逆転下では奇数である.
科学分野:
- 凝縮物質物理学
- 材料科学
- 量子材料について
背景:
- 強い電子の相互作用が 金属の対称性のない相を誘導します
- 強いスピン-軌道結合を持つ相関金属の不安定性は十分に研究されていない.
- Cd2Re2O7は金属のピロクロール物質である.
研究 の 目的:
- 強いスピン軌道結合を持つ相関金属の不安定性を調査する.
- 金属のピロクロールに 新しい電子相を発見するために
- Cd2Re2O7における新しい多極性ネマティック相を特徴づける.
主な方法:
- 空間的に解明された第二ハーモニック光学アニソトロピー測定.
- 多極ネマティック・オーダーパラメータの批判的行動の分析
- 熱相変換の調査
主要な成果:
- Cd2Re2O7で物質の多極性ネマティック相が発見された.
- この相は回転対称性を破るが,変換不変性を保持する.
- 多極ネマティック・フェーズは,スピン・オービタ・カップリングによって可能となる空間逆転下では奇数である.
- この相は,熱相転換を200K近くまで駆動する.
- パリティを壊す格子歪みは二次的な順序として発生します.
結論:
- 多極ネマティック相はCd2Re2O7における新しい物質状態である.
- スピン・オービタ・カップリングは この偶数相の出現に不可欠です
- 発見された相は,金属における電子相関とスピン軌道結合効果に関する新しい洞察を提供します.
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