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Updated: Jun 14, 2025

10:42
Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
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229m Th核同位体移行と87Sr原子時計の周波数比
Chuankun Zhang1,2,3, Tian Ooi4,5,6, Jacob S Higgins4,5,6
1JILA, University of Colorado Boulder, Boulder, CO, USA. chuankun.zhang@colorado.edu.
Nature
|September 4, 2024
まとめ
研究者たちはトリウム229を用いた 核時計を開発し 核時計と原子時計を 初めて結びつけました この突破により 次世代の精度計測と 基礎物理学の研究が可能になりました
科学分野:
- 核物理学
- 原子物理学
- 精密メトロロジー
- 量子光学
背景:
- 光学的な原子時計は 精密な計時のために 電子的なエネルギーレベルを利用します
- 核エネルギーレベルに基づいた核時計は 計測学と基礎物理学の新しいプラットフォームを提供します
- トリウム-229 (229Th) 核は,核時計に適した低エネルギー移行をしていますが,その性質については詳細な研究が必要です.
研究 の 目的:
- 229Th同位体の量子状態解像度スペクトロスコピーを実行する.
- 229Th核時計の絶対的な移行周波数を決定する.
- 核時計と原子時計の間の 直接的な周波数リンクを確立する
主な方法:
- 真空紫外線 (VUV) 周波数カムを使用して,固体CaF2ホストにおける229Th核移行を刺激した.
- JILA87Sr原子時計の 周波数を安定させました
- VUVの範囲に一貫したアップコンバージョンをするために,フェムト秒の強化カビーを使用しました.
主要な成果:
- 229Th核時計の絶対的な移行周波数を決定した.
- 229Th核の移行と87Sr原子時計の間の周波数リンクを確立しました.
- 正確に核四極分裂を測定し,229Th同位体の固有の性質を抽出した.
結論:
- 最初の固体核光学時計を デモンストレーションしました
- 核時計と原子時計の 比較を初めて成し遂げ 基礎物理学の研究の道を開いた
- この研究は精度計測,超高速物理,核物理を統合しています.
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