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単一の電子のスピンと電場との一貫した制御
K C Nowack1, F H L Koppens, Yu V Nazarov
1Kavli Institute of Nanoscience, Delft University of Technology, Post Office Box 5046, 2600 GA Delft, the Netherlands. k.c.nowack@tudelft.nl
Science (New York, N.Y.)
|November 3, 2007
まとめ
研究者らは,電場を用いた量子ドットにおける単一電子のスピンの電気制御を実証した. このブレークスルーにより,高速で一貫したスピン操作が可能になり,スピン量子ビットの完全電気制御への道を開く.
科学分野:
- 量子情報科学とは,量子情報科学である.
- 凝縮物質物理学 凝縮物質物理学
- 量子コンピューティング
背景:
- スピンベースの量子情報処理は,正確なスピン操作に依存しています.
- オンチップの統合とスケーラビリティのために,電気制御は非常に望ましい.
- 以前の方法は,しばしば磁気制御に依存しており,これは小型化にはあまり実用性がありません.
研究 の 目的:
- 実験的に,電場を使用して単一の電子スピンの一貫した制御を達成するために.
- スピン量子ビットの完全電気操作の実現可能性を調査する.
- 電気的に誘発されたスピン移行の根本的なメカニズムを探求する.
主な方法:
- 局所ゲートによって生成される振動する電場を利用して,量子ドットにおける単一の電子のスピンを制御する.
- ラビ振動を観察して,スピン移行の速度と一貫性を定量化します.
- 電気回転制御を媒介するスピン軌道相互作用の役割を分析する.
主要な成果:
- 振動する電場による単一電子スピンの一貫した制御が実証された.
- 約55ナノ秒で高速回転 (90度) を達成しました.
- 電気的に誘発されたスピン移行の鍵となるメカニズムとしてスピン軌道相互作用を特定しました.
結論:
- スピン量子ビットの完全電気操作の実現可能性を確立した.
- 電場を用いた単一のスピンの迅速かつ一貫した制御を示した.
- この研究は,スケーラブルでオンチップの量子情報処理に向けた重要な一歩です.
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