量子多体系における絡み込みエントロピーの測定
Rajibul Islam1, Ruichao Ma1, Philipp M Preiss1
1Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Nature
|December 4, 2015
まとめ
研究者は量子干渉を用いて 移動粒子における空間的な絡み合いを測定しました この突破により 複雑な多体系における 量子純度と 絡み合いのエントロピーの 直接的な測定が可能になりました
科学分野:
- 量子力学について
- 量子情報科学
- 凝縮物質物理学
背景:
- 量子現象の"つである 絡み合いは非局所的相関を記述します
- 絡み合いを測定することは,特に相互作用する非局所化粒子のシステムでは困難です.
- このようなシステムにおける空間的な絡み合いに関する直接的な実験的な測定は 難解である.
研究 の 目的:
- 移動粒子システムにおける空間的な絡み合いを測定する方法を開発する.
- 強く相関する多体系における絡み合い特性の直接的な実験測定を可能にする.
- 量子相とダイナミクスを特徴づけるための絡み合い測定を活用する.
主な方法:
- 量子干渉を用いて 絡み合いを測定した.
- 光学格子における超冷たいボゾン原子の単位の解像度制御を用いる.
- 多体状態の2つの同一のコピーを用意して 干渉した.
主要な成果:
- 量子純度,レニーの絡み合いのエントロピー, 相互情報の測定に成功しました
- 空間的な絡み合いを定量化するための新しい実験的アプローチを示した.
- 複雑なシステムの量子相関を研究するための新しいツールを提供しました.
結論:
- 開発された方法は,複雑な多体系における絡み合いの直接的な測定を可能にします.
- この技術は 量子相とダイナミクスを 絡み合いを用いて特徴づけるための道を開きます
- 量子情報科学と凝縮物質物理学の分野を進める
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