量子ドット分子における量子状態の結合と絡み合い

M Bayer¹, P Hawrylak, K Hinzer

¹Physikalisches Institut, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany. mbayer@physik.uni-wuerzburg.de

Science (New York, N.Y.)

|February 13, 2001

まとめ

量子ドットで量子状態をペアリングし,エンタグリングする方法を示します. 相互作用によって引き起こされたエネルギー分裂は,電子穴複合体が絡み合ったスピン状態に相当することを確認します.

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:

量子ドットは,調節可能な電子特性を持つ半導体ナノ結晶です.
結合量子ドットシステムにおける量子状態を理解することは,量子情報処理において極めて重要です.

研究の目的:

縦に並べられた量子ドットで量子状態の結合と絡み合いを示すために.
ドット分離の関数としてエクシトンの相互作用誘発エネルギー分裂を調査する.

主な方法:

単一のドット分子の相互作用する電子穴対 (エクシトン) の放出を研究する.
垂直に並べられた量子ドット間の分離距離を変化させる.

主要な成果:

4nmのドット層分離で30meVを超えるエクシトンの相互作用誘発エネルギー分裂を観察しました.
ダブル・ドット・システムにおける粒子のトンネリングを単回転問題にマッピングした.
電子穴複合体は,2つの相互作用するスピンの絡み合った状態に相当します.

結論:

垂直に並べられた量子ドットは,量子状態をカップル化し,絡めるために使用できます.
観察されたエクシトン分裂は,絡み合いの証拠を提供します.
このシステムは,量子コンピューティングアプリケーションのための潜在的なプラットフォームを提供します.

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