量子プロジェクションの限界より100倍低い測定ノイズ
Onur Hosten1, Nils J Engelsen1, Rajiv Krishnakumar1
1Department of Physics, Stanford University, Stanford, California 94305, USA.
Nature
|January 12, 2016
まとめ
この研究は87Rb原子の量子絡みを示し,標準量子限界を超える測定精度を大幅に改善しました. この進歩は原子時計の精度を高め 基礎物理学の研究にも応用できます
科学分野:
- 量子メトロロジー
- 原子物理学
- 量子光学
背景:
- 量子メトロロジーは量子エンタグリングを活用して 測定精度を高めます
- 非相関粒子から発生するショットノイズは,精度を標準量子限界 (SQL) に制限します.
- 絡み合った探査粒子は ショットノイズを軽減し,ハイゼンベルクの限界に達する可能性があります.
研究 の 目的:
- 最適化された従来のシステムに優れている性能を達成する量子計量アプローチを実証する.
- スピン圧縮された原子集合を用いて計測学的改善を調査する.
- 原子時計のような応用のための量子強化測定の可行性を評価する.
主な方法:
- 半百万個の87Rbの原子を"時計"状態で利用する.
- 旋回圧縮を実現するために,光学空洞ベースの測定を使用します.
- マイクロ波による回転を測定し,相解像度を定量化する.
主要な成果:
- 原子組で20.1 ± 0.3デシベル (100倍) のスピン圧縮を達成した.
- 解像度回転は,SQLを超えて18.5 ±0.3デシベル (70倍) です.
- 147ミクロラディアンの単発相解像度を示し 最先端の冷たい原子センサーを上回った
- 680 ± 35 以上の粒子が絡み合っている.
結論:
- 量子メトロロジーのアプローチは前例のないメトロ学的な改善をもたらします
- この方法は原子時計や慣性センサーや 基礎物理学のテストの強化の可能性を示しています
- 量子力学で強化された原子時計の測定は 微波源のノイズによって制限された 11倍の改善を達成しました
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