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エネルギー交換なしに単一の原子の内部状態を測定する
Jürgen Volz1, Roger Gehr, Guilhem Dubois
1Laboratoire Kastler-Brossel, ENS, CNRS, Université Pierre et Marie Curie - Paris 6, 24 rue Lhomond, 75005 Paris, France.
Nature
|July 15, 2011
まとめ
研究者は,最小限のエネルギー交換で原子量子ビットを測定するための新しい方法を実証しました. このテクニックは,光学空洞を使用して,1つ未満の自発的な散乱イベントを持つ原子を検出し,量子情報処理を改善します.
科学分野:
- 量子物理学とは,量子物理学のことです.
- 原子物理学 原子物理学とは
- 量子情報科学とは,量子情報科学である.
背景:
- 量子測定は本質的に反作用を引き起こし,測定された状態を変更します.
- フリースペース光学検出のような従来の方法は,かなりの自発的な散乱を誘導し,エネルギー交換 (加熱) につながります.
- このエネルギー交換は,量子情報処理における量子ビットの効率と再利用性を制限する.
研究 の 目的:
- 原子量子ビットの光学検出を実験的に実証し,自発的な散乱を大幅に減少させる.
- 情報の獲得と自発的な放出を定量的に測定する.
- エネルギー交換のない体制における量子測定の反作用を特徴づけるために.
主な方法:
- 単一の原子を検出するために光学腔を利用する.
- 光の透過と反射を穴を通して測定する.
- 測定中に発生した自発的な散乱現象を定量的に評価する.
- 測定の反作用を分析するために量子ゼノ型実験を実行する.
主要な成果:
- 原子量子ビットの検出は,平均で0.2未満の自発的な散乱イベントで達成されました.
- 10%未満の検出エラー率を得ました.
- 量化測定の反作用で,インシデント光子毎のほぼ完全な状態崩壊を示しています.
- "エネルギー交換なし"のシステムでの量子測定を実証しました.
結論:
- 開発された方法は,量子測定中のエネルギー交換を大幅に削減します.
- このアプローチは,単純化された中性原子量子計算への道を開きます.
- 潜在的応用には,閉じた移行のない分子や原子の感受性検出が含まれます.
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