離散時間結晶の観測
J Zhang1, P W Hess1, A Kyprianidis1
1Joint Quantum Institute, University of Maryland Department of Physics and National Institute of Standards and Technology, College Park, Maryland 20742, USA.
Nature
|March 10, 2017
まとめ
科学者たちは 物質の新たな段階である 離散的な時間結晶を 実験的に観測しました この新しい状態は,非均衡のシステムで持続的な時間相関を示し,時空現象を研究するための扉を開きます.
科学分野:
- 物理学
- 凝縮物質物理学
- 量子力学
背景:
- 自発的な対称性破裂は物理学において極めて重要であり,結晶形成 (空間対称性破裂) を例示する.
- 時間の変換対称性を破るタイムクリスタルが提案されましたが,熱の均衡では禁止されています.
- 非均衡のフロッケシステムは,サブハーモニックタイムレスポンスを示し,離散時間結晶の概念につながります.
研究 の 目的:
- 実験的に観察し,時間結晶の存在を確認する.
- この新しい段階の物質の性質と強さを調べるため
主な方法:
- 捕まった原子イオンの 相互作用するスピンチェーンを利用します
- 周期的なハミルトン駆動を多体局所条件下でシステムに適用する.
主要な成果:
- 離散時間結晶の実験観察
- 持続的な時間相関を示している.
- 観測された現象は,外部の干渉に対して安定しています.
結論:
- 離散時間結晶の実験的実現は,非均衡のシステムにおけるその存在を確認します.
- この発見により,長距離の空間時間的な相関関係を持つシステムの研究が可能になった.
- 本質的に不均衡な条件下で 物質の新たな相を探求する道を開くのです
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