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ジョセフソン環調節器による量子限界に近い相保存増幅
N Bergeal1, F Schackert, M Metcalfe
1Department of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520-8284, USA. nicolas.bergeal@espci.fr
Nature
|May 7, 2010
まとめ
研究者らは,量子情報処理に不可欠な相情報を保存する新しい超伝導パラメトリック増幅器を開発した. このフェーズ保存増幅器は,量子制限に近いノイズ性能を達成し,量子技術の新たな道を開きます.
科学分野:
- 量子情報処理 量子情報処理
- 超伝導装置の超伝導装置について
- マイクロ波の増幅器 マイクロ波の増幅器
背景:
- 固体量子情報処理には,量子限定の増幅器や周波数変換器が必要です.
- 線形増幅器は,相感度または相保存に分類され,異なるノイズ特性を持っています.
- 段階保存増幅器は非常に望ましいものですが,入手できませんでした.
研究 の 目的:
- 本質的に相保の超伝導パラメトリック増幅器を実験的に実現する.
- マイクロ波信号に対して量子的に制限された性能を持つ装置を実証する.
- 量子アナログ信号処理における新しいアプリケーションを可能にする.
主な方法:
- ホイットストーン・ブリッジの構成で4つのジョセフソン・ジャンクションを備えたジョセフソン・リング・モジュールを使用した.
- 非変性パラメータ増幅スキームを実装しました.
- 新しいノイズソースを使用して,増幅器の増益,帯域幅,およびノイズ特性を特徴付けました.
主要な成果:
- 段階保存型超伝導パラメトリック増幅器を成功裏に実現しました.
- 分析的な予測と一致した獲得と帯域幅の特徴を達成しました.
- 動作条件下における量子限界の3倍の全システムノイズの上限を示した.
結論:
- 開発されたジョセフソン・リング・モジュレーター・アンプは,本質的にフェーズ保存です.
- このデバイスは,量子アナログ信号処理アプリケーションに重要な進歩をもたらします.
- 潜在的な応用には,量子非破壊読み出し,量子フィードバック,および絡み合ったマイクロ波ペア生成が含まれます.
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