21世紀初頭における時間と周波数の基準
S A Diddams1, J C Bergquist, S R Jefferts
1Time & Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, CO 80305, USA. sdiddams@boulder.nist.gov
まとめ
電子レンジのセシウム原子時計は,10^15.10分の1以下で比類のない精度を提供します. 新興の光学原子時計は,科学技術におけるタイムキーピングのさらに大きな進歩を約束しています.
科学分野:
- 物理 物理学 物理学とは
- メトロロジー・メトロロジー
- 原子物理 原子物理学
背景:
- マイクロ波原子時計,特にセシウム基の原子時計は,50年の開発を経て,10^15分の1未満の分数不確実性に達しています.
- このレベルの精度は,現在,計量学の分野では比類のないものです.
- 原子時間および周波数規格は,多くの社会的応用と科学的探査に不可欠である.
研究 の 目的:
- 原子時間および周波数基準の現在の最先端状態をレビューする.
- 光学原子時計の進歩とその潜在的な影響について議論する.
- 科学・技術におけるこれらの規格の多様な応用を強調する.
主な方法:
- 電子レンジと光学原子時計に関する既存の文献と研究のレビュー.
- パフォーマンスメトリックの分析,特に分数的な不確実性.
- さまざまな分野における現在のおよび潜在的なアプリケーションの探索.
主要な成果:
- セシウムマイクロ波原子時計は,10^15.10分の1未満の分数不確実性を達成しています.
- 光学原子時計は,過去5年間で加速的な発展を遂げており,タイムキーピングの強化の可能性を示しています.
- 原子時間および周波数基準は,近代技術と基礎科学の不可欠な部分です.
結論:
- 電子レンジと光学の両方の原子時計は,計測学の頂点を達成しています.
- 継続的な開発は,精度およびより広範なアプリケーションのさらなる改善を約束します.
- これらの基準は,技術的進歩と科学的発見の限界を押し広げるために不可欠です.
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