リアルタイムの量子フィードバックは,光子数の状態を準備し,安定させます
Clément Sayrin1, Igor Dotsenko, Xingxing Zhou
1Laboratoire Kastler Brossel, ENS, UPMC-Paris 6, CNRS, 24 rue Lhomond, 75005 Paris, France.
Nature
|September 3, 2011
まとめ
この研究は,超伝導体空洞内のマイクロ波場を安定させ,光子数の状態を準備し,デコヘレンスを逆転させるためのリアルタイム量子フィードバックを実証しています. これにより,複雑な量子情報操作の量子制御が進歩する.
科学分野:
- 量子物理学とは,量子物理学のことです.
- 量子制御とは,量子制御のことです.
- 超伝導回路は,超伝導回路である.
背景:
- 古典的なフィードバックループは,センサーの出力をセットポイントと比較することによってシステムを安定させます.
- 量子フィードバックは,量子状態に対する測定反射による課題に直面しています.
- 弱い測定は,情報獲得とシステムの混乱の間の妥協を提供します.
研究 の 目的:
- マイクロ波場のリアルタイム安定化量子フィードバックループを実装する.
- 要求に応じて光子数状態 (フォック状態) を準備する.
- 量子振動器におけるデコエレンス効果に対抗するため.
主な方法:
- リアルタイムのコンピュータ制御フィードバックシステムを活用した.
- 原子ビームセンサーを用いた弱い量子非破壊測定を用いた.
- クラシックフィールドを注入するアクチュエータを導入し,マイクロ波フィールドの状態を調整しました.
主要な成果:
- 超伝導体腔内のマイクロ波場の光子数値状態を成功裏に準備した.
- デコヘレンスの誘発による量子ジャンプの逆転を実証した.
- 非古典的な状態を生成し,非相関性に対抗するアクティブ・コントロールの能力を示した.
結論:
- この実験は,複雑な量子情報操作を実装するための重要な一歩を表しています.
- リアルタイムの量子フィードバックは,量子システムをデコエレンスに対して積極的に安定させることができます.
- この研究は,高度な量子メモリと量子バスアプリケーションの道を開く.
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