トラッキングフォトンのジャンプは,量子非破壊対数測定を繰り返し行います
L Sun1, A Petrenko2, Z Leghtas2
11] Departments of Applied Physics and Physics, Yale University, New Haven, Connecticut 06511, USA [2] Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, China (L.S.); Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, A-6020 Innsbruck, Austria and Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Otto-Hittmair-Platz 1, A-6020 Innsbruck, Austria (G.K.).
Nature
|July 22, 2014
まとめ
研究者らは,エラーシンドロームの高速で繰り返された量子非破壊測定を実証している. この重要なステップは,堅牢な量子コンピュータを構築し,量子情報を保護するために,量子エラー訂正を前進させる.
科学分野:
- 量子コンピューティング
- 量子情報科学とは,量子情報科学である.
- 量子エラー補正 量子エラー補正
背景:
- 量子情報は脆弱であり,実用的な量子コンピュータには量子エラーの修正が必要である.
- 量子エラーの修正には,暗号化された量子情報に干渉することなく,観測可能 (エラーシンドローム) を監視する必要があります.
- 以前の方法では,量子エラー修正の重要な要件であるエラー症候群の迅速かつ繰り返し監視が欠けていました.
研究 の 目的:
- 量子エラーシンドロームの素早く繰り返された量子非破壊 (QND) 測定を実証する.
- 保護された量子メモリスキームに関連するマイクロ波腔のQNDパリティトラッキングを実装する.
主な方法:
- 操作と測定のために,マイクロ波腔の光子数パリティをアンキラ量子ビットにマッピングしました.
- 協調的な状態が偶数または奇数キャット状態に崩壊することを観察するために投影的な測定を行った.
- 高い単発精度で量子非破壊測定技術を活用しました.
主要な成果:
- フォトン数パリティの量子ジャンプを成功裏に追跡し,キーエラー症候群である.
- 測定毎にパリティを変化しないまま残す確率は99.8%で,投影的な測定が実証されています.
- 穴の寿命より速い測定速度を達成しました.
結論:
- 証明された量子非破壊対数追跡は,アクティブ量子エラー修正の重要な進歩です.
- このテクニックは,決定的なキャットステートエンコーディングと組み合わせて,量子ビットの寿命を延長するために不可欠です.
- これは,故障耐性量子コンピュータと保護された量子メモリを構築するための重要なステップです.
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