Nonequilibrium dynamics of cold atoms with long-range interaction in optical lattices

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K03472
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 13010:Mathematical physics and fundamental theory of condensed matter physics-related
• Research Institution: Kindai University
• Principal Investigator: Kasamatsu Kenichi 近畿大学, 理工学部, 准教授 (70413763)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 冷却原子 / ボースアインシュタイン凝縮 / 光格子 / 長距離相互作用

Outline of Final Research Achievements

Targeting the non-equilibrium dynamics in cold atomic gases, we have tackled various problems of many-body quantum dynamics by adjusting the degree of quantum fluctuation, from the mean-field approximations to the analyses that accurately incorporate quantum fluctuations. In the case of strong quantum fluctuations, we clarified a phenomenon called quasi many-body localization exhibited by polar gases with long-range interactions in an optical lattice. In the case of weak quantum fluctuations, we studied the motion of dark solitons in Bose-Einstein condensates in an optical lattice, showing that there is the classical-quantum crossover. In the two-component Bose gas in an optical lattice, we showed that the quantum droplet can be induced by strong quantum fluctuations.

Free Research Field

物性理論

Academic Significance and Societal Importance of the Research Achievements

超低温下にある冷却原子系では、物理を調べる理想的な環境が準備され、系のほぼ全てのパラメーターの制御も可能であるため、様々な物性や量子ダイナミクスを基本的立場から検証することが可能である。本研究で得られた知見は新しい実験研究の更なる動機となり、量子論や物性論の発展に大いに貢献すると期待される。