113 km 以上の 10−19 不安定性を持つ時間と周波数の自由空間拡散
Qi Shen1,2,3, Jian-Yu Guan1,2,3, Ji-Gang Ren1,2,3
1Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences, University of Science and Technology of China, Hefei, China.
Nature
|October 5, 2022
まとめ
研究者は,前例のない113kmの空間のリンク上で正確な時間周波数拡散を達成し,4×10−19の不安定性に達しました. この画期的な発見により グローバルな光学ネットワークと 将来の衛星計時が可能になります
科学分野:
- 物理学
- メトロロジー
- 光学工学
背景:
- 光学時計のネットワークは 航海,秒の定義変更,重力テストに不可欠です
- 現在の光学時計は 10−19 レベルでの周波数不安定を達成します.
- グローバル光学ネットワークは,長距離のフリースペースリンクに類似した性能を必要とし,以前は数十キロメートルを超えて達成されませんでした.
研究 の 目的:
- 高精度な時間周波数拡散を 長距離の空間のリンクで実証する.
- 113kmで10−19の不安定性を達成する.
- 世界規模の光学ネットワークの実現可能性を確立する.
主な方法:
- 高周波のを使いました
- 高安定性と高効率の光学トランシーバーシステムを採用しています.
- 効率的な線形光学サンプリング技術
主要な成果:
- 6.3 × 10−20 ± 3.4 × 10−19のオフセットで時間周波数拡散を達成した.
- 113kmの空間のリンク上で,10,000秒で4 × 10−19未満の不安定性を示した.
- 最低89dBのチャンネル損失で安定性を維持している.
結論:
- 報告された技術は,前例のない長距離自由空間時間周波数拡散を可能にします.
- この進歩は,地上でのアプリケーションと将来の衛星時間周波数拡散に不可欠です.
- この研究は,高性能な時間拡散を持つグローバルな光学ネットワークの基礎を築きます.
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