量子ドットにおける個々の電子のスピンの単発読み出し

J M Elzerman¹, R Hanson, L H Willems Van Beveren

¹Kavli Institute of Nanoscience Delft and ERATO Mesoscopic Correlation Project, Delft University of Technology, PO Box 5046, 2600 GA Delft, The Netherlands.

Nature

|July 23, 2004

まとめ

研究者は,半導体量子ドット内の個々の電子スピンの最初の電気単発測定を実証しました. この量子情報科学の突破は,スピン状態を電気的に読むための新しい方法を提供します.

科学分野:

量子物理学とは,量子物理学のことです.
凝縮物質物理学凝縮物質物理学
ナノテクノロジーナノテクノロジー

背景:

スピンは,電子のような素粒子の基本的な量子力学的性質である.
個々のスピンは量子情報処理に不可欠ですが,電気的な読み出しは依然として課題です.
単一スピンの現在の読み出し方法は,主に光学または力顕微鏡に基づいています.

研究の目的:

個々の電子のスピン状態の電気的単発測定のための新しい方法を実証する.
量子情報アプリケーションの既存の読み出し技術の限界を克服するために.
半導体量子ドットにおける電子スピンを量子情報のために使用する可能性を評価する.

主な方法:

半導体量子ドットにおける個々の電子のスピン状態の電気単発測定.
量子ドットに閉じ込められた単一の電子のスピンから電荷への変換を利用する.
センシティブな量子点コンタクト検出器を使用して単一電子の電荷を検出します.

主要な成果:

個々の電子のスピン状態の電気単発測定が成功しました.
スピン測定の可視性は約65%であることが示されています.
単回転エネルギー放松時間が非常に長い (8Tで0.85msまで) 観測されました.

結論:

半導体量子ドットにおける単一の電子のスピンの電気的な読み出しは,今や達成可能である.
実証された技術と長いリラクゼーション時間は,量子情報アプリケーションにとって有望である.
この研究は,電子のスピンを利用したスケーラブルな量子コンピューティングアーキテクチャの道を開く.

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