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シリコンでコードされたスピンクビットを持つ普遍的な論理
Aaron J Weinstein1, Matthew D Reed2, Aaron M Jones2
1HRL Laboratories, LLC, Malibu, CA, USA. ajweinstein@hrl.com.
Nature
|February 6, 2023
まとめ
電子のスピンを電気的に制御し マイクロ波によるエラーを克服する 新しい量子計算方法を開発しました このアプローチは 誤差を許容する量子計算と 性能の向上への有望な経路を提供します
科学分野:
- 量子コンピューティング
- 量子情報科学
- 固体物理学
背景:
- 量子コンピューティングはノイズと不完全な制御によるエラーにより課題に直面し,故障耐性を阻害します.
- 量子ビットのマイクロ波制御によって引き起こされる相関エラーは,多くの量子ビット技術にとって重要な障害です.
- 既存の方法は,誤差を許容する量子計算のための厳格なエラー特徴と相関管理を必要とします.
研究 の 目的:
- 量子計算の代替方法として,エネルギーが劣化した量子ビット状態を用いる.
- 微波に関連した誤差源を回避して 普遍的な量子制御を実現する
- 量子コンピューティングにおけるスケーラブルな故障耐性を探求する.
主な方法:
- 部分スピンスワップのための近隣コンタクトインタラクションによって制御されるエネルギー退化型エンコードされた量子ビット状態を使用した.
- 完全電気制御を可能にする部分スワップの調整されたシーケンスに電圧パルスを使用します.
- 拡張可能なプラットフォームで28Si/SiGeの量子ドットを使って 6ビット配列を製造した.
主要な成果:
- 2つのエンコードされた量子ビットの 普遍的な量子制御を達成し マイクロ波関連の相関エラーを回避しました
- インターリーブ・ランダム・ベンチマークを用いて定量化された運用精度:96.3% ±0.7% 暗号化されたCNOT, 99.3% ±0.5% 暗号化されたSWAP.
- 高い量子コヘランスと 低クロスストーク制御を 部分スワップ操作で証明した.
結論:
- 部分スワップを用いた全電気制御法が開発され,故障耐性量子計算への強力な経路を提供している.
- 濃縮シリコンの量子コヒーレンスと 電気制御と エラー無感のエンコーディングは 量子コンピューティングの重要な課題を解決します
- このアプローチは,スケーラブルな故障耐性を達成し,計算上の優位性を解き放つための強力な基盤を提供します.
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