光学的な原子時計のトランジションの絡み合い
Edwin Pedrozo-Peñafiel1, Simone Colombo1, Chi Shu1,2
1Department of Physics, MIT-Harvard Center for Ultracold Atoms and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA.
Nature
|December 17, 2020
まとめ
研究者は,光学格子時計 (OLC) で多くの原子が絡み合っている状態を作り,標準量子限界 (SQL) を超える性能を達成しました. 量子計測学のこの突破は 原子時計の安定性と精度を 将来の科学的な応用のために高めています
科学分野:
- 量子測定法
- 原子物理学
- 精度測定
背景:
- 最先端の原子時計は,光学格子時計 (OLC) を含め,原子レベル間の精密なエネルギー差測定に依存しています.
- OLCの安定性は,局所振動器のレーザーノイズ (ディックノイズ) と測定量子ノイズからの標準量子限界 (SQL) によって制限されます.
- 以前のエンタグレメントを用いてSQLを上回る試みは,より不安定なマイクロ波時計に限られ,光学クロックトランジションの実験的な実証はありませんでした.
研究 の 目的:
- 光学格子クロックトランジションの絡み合いの生成を実験的に実証する.
- 光学格子時計を 標準の量子限度を超えて操作する
- タイムメーキングの精度と精度を向上させるためのエンタグリングの可能性を紹介する.
主な方法:
- イテルビウム-171の光学格子クロック移行を利用した多原子の絡み合いの状態の作成.
- 絡み合った原子アンサンブルを用いたラムゼイ配列の実装.
- 時計の安定性を評価し,SQLとの性能を比較するためにアラン偏差の測定.
主要な成果:
- 局所振動器のノイズを考慮した後に,SQL以下のアラン偏差を持つラムゼイ配列を証明した.
- 数百個のイテルビウム-171原子の集合を用いて,SQLに対する[Formula: see text]デシベルのメトロロジカル・ゲインを達成した.
- 巻き込みによる平均化時間の2.8 ± 0.3分の1の縮小が観察され,時計の性能が向上したことを示した.
結論:
- この研究は,OLC移行で多原子絡み合いの状態の作成を成功裏に実証し,SQLを超えた操作を可能にします.
- 最先端の光学格子時計の性能を大幅に改善する 有効な経路を提供する.
- この進歩により 時計の精度と精度が向上し 物理学の基礎テストや 地位測量や 重力波検出に 影響を及ぼすことが期待されます
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