超伝導量子ビットの単一の量子軌道を観測する
K W Murch1, S J Weber, C Macklin
1Quantum Nanoelectronics Laboratory, Department of Physics, University of California, Berkeley, California 94720, USA. steppenbeck@cns.s.u-tokyo.ac.jp
Nature
|October 11, 2013
まとめ
環境モニタリングは,量子軌道を追跡することによって,量子デコエレンスを軽減することができます. この研究は,超伝導量子ビットのリアルタイム測定を実証しています.
科学分野:
- 量子物理学とは,量子物理学のことです.
- 量子情報科学とは,量子情報科学である.
- 超伝導回路について
背景:
- 量子システムは,環境の相互作用によってスーパーポジション状態を失い,その過程をデコエレンスと呼びます.
- デコヘレンスは純粋な量子状態を統計的混合物に変換し,量子計算と情報処理を制限する.
- リアルタイム環境測定は,量子純度を維持し,システムの進化を制御するための潜在的な経路を提供します.
研究 の 目的:
- 環境モニタリングを通じた非相干性の緩和を実験的に実証する.
- 超伝導量子ビットの個々の量子軌道をリアルタイムで追跡する.
- 量子フィードバック理論を検証し,新しい量子制御機構を探求する.
主な方法:
- マイクロ波腔内の超伝導クビットを監視するために弱い測定を使用します.
- ほぼ量子限定のパラメトリック増幅器を使用して,空洞のフィールド相または振幅を選択的に測定します.
- ブロック球上の追跡された量子軌道を検証するために量子状態トモグラフィーを実行します.
主要な成果:
- 超伝導量子ビットの個々の量子軌道を成功裏に追跡した.
- 環境モニタリングが非一貫性を効果的に緩和することを実証しました.
- ブロック球の特定の経路に量子軌道が閉じ込められていることを確認しました.
結論:
- 環境モニタリングは,量子システムにおける脱コエレンスと戦うための実行可能な戦略です.
- 実験結果は,量子フィードバック制御のためのベイジアン統計を検証しています.
- この研究は,量子状態のリモート操作のための量子ステアリングを実装するための道を開きます.
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