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シリコンの核スピン量子ビットの高精度読み出しと制御
Jarryd J Pla1, Kuan Y Tan, Juan P Dehollain
1Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, New South Wales 2052, Australia.
Nature
|April 20, 2013
まとめ
研究者らは,シリコンの単一のリン-31核スピンの電気制御を実証し,量子コンピューティングのために高精度を達成しました. このブレークスルーは,高度な量子情報処理のために,電子スピン読み取りと核スピン操作を統合しています.
科学分野:
- 量子情報科学とは,量子情報科学である.
- 固体物理 固体物理学
- マイクロエレクトロニクス エンジニアリング
背景:
- 核スピン検出は,化学から医学に至るまで,多様な科学的応用に不可欠です.
- 単一の核スピンは,孤立しているため,量子情報処理に有望である.
- シリコン中の-31 (31P) 核スピンは,優れたコヘレンスを提供し,確立されたマイクロ電子工業を活用します.
研究 の 目的:
- 単一の31P核スピン量子ビットの電気検出と一貫した操作を実証するために.
- 欠陥耐性量子コンピューティングに適した高精度を達成するために.
- シリコンにおける核スピンベースの量子コンピューティングのための完全な電気制御および測定プラットフォームを確立する.
主な方法:
- シングルショット電子スピン読み出しとオンチップの電子スピン共鳴の統合.
- 量子非破壊と核スピンの電気単発読み取り.
- キュービット操作のための一貫した無線周波数パルスアプリケーション.
主要な成果:
- 核スピン読み取りの精度は99.8%を超え,固体量子ビットの中で最高を達成しました.
- イオン化された31Pドナーで60ミリ秒の核スピンコヒーレンス時間を実証しました.
- 98%以上の1クビットゲート制御フィデリティを達成しました.
結論:
- シリコンの単一の31P核スピンは,電気的に制御され,高精度で読み取ることができます.
- シリコンマイクロエレクトロニクス技術は,核スピンベースの量子情報処理に適応することができます.
- この研究は,固体量子ビットを使用して,スケーラブルで故障耐性のある量子コンピューティングのための実行可能なプラットフォームを提示します.
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