Quantum many-body dynamics explored by strongly correlated Rydberg electron wave packets

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K14365
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Atomic/Molecular/Quantum electronics
• Research Institution: Kyoto University (2018); Institute for Molecular Science (2017)
• Principal Investigator: Takei Nobuyuki 京都大学, 理学研究科, 特定准教授 (20531841)
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 量子光学 / 原子物理 / 量子エレクトロニクス / コヒーレント制御

Outline of Final Research Achievements

Our two unique tools of ultrafast coherent control technique with attosecond precision and a strongly correlated ultracold Rydberg gas are applied to an important concept of symmetry breaking. Laser pulses can break the electronic structure symmetry of atoms and molecules by preparing a superposition of states with different irreducible representations. We discovered the reverse process, symmetry restoration, by means of two laser pulses. Symmetry restoration is achieved if the time delay is chosen such that the superposed states have the same phases at the temporal center. This condition must be satisfied with a precision of a few attoseconds. The experimental feasibility of symmetry restoration is demonstrated by means of high-contrast time-dependent Ramsey interferometry of the 87Rb atom. The demonstrated technique is useful to understand quantum many-body dynamics in a strongly correlated ultracold Rydberg gas.

Free Research Field

量子光学

Academic Significance and Societal Importance of the Research Achievements

量子シミュレータは古典計算機では計算することが難しい強相関系の量子多体問題を解明するのに強力なツールであり、基礎学術のみならず新機能性材料の開発への貢献など応用面においても非常に期待されている。私たち独自のシステムは、より強相関な状態を生成し易く、またそれが示す多体ダイナミクスを観測・制御できるため、量子多体問題の深い理解に有用であると期待される。今回実証した電子構造の対称性の破れとその回復技術は、量子シミュレータへの応用のみならず、分子間の化学反応や分子中の電荷移動の制御にも応用可能と考えられる。