調節可能な相互作用する複合フェルミオン相,半満たされた二重層-グラフェン・ランドーレベル
A A Zibrov1, C Kometter1, H Zhou1
1Department of Physics, University of California, Santa Barbara, California 93106, USA.
Nature
|September 22, 2017
まとめ
研究者は,グラフェンヘテロ構造における堅固な偶項分数量子ホール (FQH) 相を観察した. この発見は非アベルのアニオンと トポロジカルクビットの研究のための調整可能なプラットフォームを提供します.
科学分野:
- 凝縮物質物理学
- 量子情報科学
背景:
- 非アベルのアニオンは トポロジカル・クビットにとって鍵となるもので,デコヘレンスに対する保護を提供する.
- 偶項分数量子ホール (FQH) 状態は,これらのアニオンをホストすると予測されていますが,実験的な制限があります.
研究 の 目的:
- 実験的に観察し,堅固な偶数 FQH 段階を特徴づける.
- 非アベルのアニオンとその性質を研究するための調整可能なプラットフォームを確立する.
主な方法:
- 二重ゲート,六角ボロン-ニトリド-カプセル化された二層グラフェンヘテロ構造の製造.
- キャリア密度,層の極化,磁場を正確に制御する.
- エネルギーギャップと相変化の測定
主要な成果:
- 半整数のランドーレベルの充填で堅固な偶数のFQH相の観測.
- エネルギーギャップが大きくなり (以前の3倍)
- ペアリングされたPfaffianフェーズと連続したフェーズ移行の観測のための証拠.
結論:
- グラフェンヘテロ構造は,FQH物理学の原始的で調整可能なプラットフォームを提供します.
- これらの発見は,これらのシステムにおける非アベルの量子ビットの検出の可能性を裏付けています.
- トポロジーと量子批判性のさらなる研究を可能にします.
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