単層の限界まで独立する結晶酸化ペロブスキート
Dianxiang Ji1,2, Songhua Cai1,2, Tula R Paudel3,4
1National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory of Artificial Functional Materials, College of Engineering and Applied Sciences, Nanjing University, Nanjing, China.
Nature
|June 7, 2019
まとめ
研究者は,新しい二次元 (2D) 電子相の探索を可能にするために,独立した超薄のペロブスキートフィルムを作成しました. BiFeO3フィルムは2Dの限界で巨大な四角性と偏りを示しています.
科学分野:
- 材料科学
- 凝縮物質物理学
- 固体化学
背景:
- グラフェンのような二次元 (2D) 材料は単層に薄めるとユニークな電子特性を発揮します.
- トランジション金属酸化物ペロブスキットは,多種多様な相関電子相を大量に保持することが知られている.
- 2次元ペロブスキート材料で これらの相を調査すると 奇妙で未知の現象が明らかになります
研究 の 目的:
- 高結晶質の超薄ペロブスキートフィルムを製造する.
- この2Dペロブスキート材料の電子的および構造的性質を調査する.
- 新しい2D相関電子フェーズを作成する可能性を実証する.
主な方法:
- ユニットセルレベルまで独立したペロブスキート膜 (SrTiO3,BiFeO3) を犠牲バッファ層 (Sr3Al2O6) を使用して合成する.
- フィルム沈殿のための反応性分子ビームエピタキシ
- シリコン・ウェイファーや炭素・フィルムを含む様々な基板に超薄膜を移す.
主要な成果:
- 単一ユニット細胞の厚さに近づくフリースタンドペロブスキートフィルムで高結晶質を達成した.
- 独立したBiFeO3フィルムは,2Dの限界に近い重要な,予期せぬ四角性と偏りを示した.
- 結晶の秩序を維持するための重要な厚さの欠如が,これらの独立した超薄酸化物フィルムで実証された.
結論:
- 独立した超薄ペロブスキートフィルムは,厚さの制限なしに合成され,さまざまな基板に転送できます.
- この製造能力は,2D相関電子相とインターフェイス現象の研究のための新しい道を開きます.
- この発見は 原子的に薄いペロブスキート系における 奇妙な電子の振る舞いを 探求するための道を開きます
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