絡み合いのダイナミクスの決定
O Jiménez Farías1, C Lombard Latune, S P Walborn
1Instituto de Física, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro RJ 21941-972, Brazil.
Science (New York, N.Y.)
|May 16, 2009
まとめ
研究者らは,騒音の影響を受ける2量子ビットシステムにおける量子絡まりを推定するより単純な方法を開発した. このテクニックは,複雑な状態の再構築を回避し,絡み合い評価をより効率的かつアクセシブルにします.
科学分野:
- 量子情報科学とは,量子情報科学である.
- 量子光学とは,量子光学である.
- 量子コンピューティング
背景:
- 複数の当事者の絡み合いを推定することは,量子情報処理の頑丈性にとって極めて重要です.
- 通常,これは実験的に要求される完全な量子状態トモグラフィーを必要とします.
- 不協和性は,絡み合ったシステムに重大な影響を及ぼし,効率的な評価方法を必要とします.
研究 の 目的:
- 騒々しい2量子ビットシステムにおける絡み合いダイナミクスの推定を簡素化するために.
- 最終状態の再構築の必要性を回避する方法を開発する.
- 絡み合いの強さを決定する直接的かつ効率的な方法を提供すること.
主な方法:
- 騒々しいチャネルにさらされた2量子ビットシステムにおける絡み合いのダイナミクスを調査した.
- 騒音効果を特徴付けるため,単一当事者プロセストモグラフィーを利用しました.
- 実験的に,線形光学セットアップを使用して発見を実証しました.
主要な成果:
- 単一の普遍的な曲線は,純粋な初期状態と混合初期状態の両方の絡み合いダイナミクスを正確に記述します.
- 特定の騒音条件下では,絡み合いの突然の消失が観察されました.
- 初期状態と単一パーティトモグラフィのみを使用して,絡み合いを決定するための直接的な方法を確立しました.
結論:
- 開発された方法は,絡み合い推定のための完全な量子状態トモグラフィーに効率的な代替案を提供します.
- このアプローチは,量子情報プロセスの信頼性の評価を,デコエレンスに対して強化します.
- 実験的検証は,簡素化された絡み合いの決定の実用性を確認しています.
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