Quantum Turbulence of BEC in Anti-dot optical lattices

2015 Fiscal Year Final Research Report

• Project/Area Number: 26610125
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Atomic/Molecular/Quantum electronics
• Research Institution: Kyoto University
• Principal Investigator: Kinoshita Toshiya 京都大学, 人間・環境学研究科(研究院), 准教授 (80452259)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: ボース・アインシュタイン凝縮 / アンチドット型光格子 / 動的不安定性 / 超流動 / 量子渦

Outline of Final Research Achievements

We have investigated the onset of dissipation of BEC in sinusoidally shaken Anti-dot optical lattices (ADL). The dissipation can be monitored in matter wave interference patterns, where excitations with a particular wavenumber are manifested as different spots or distributions. At low lattice heights, excitations with the wavenumber corresponding to a lattice period is generated when the shaken velocity exceeds a half of Bloch velocity. At larger heights, excitation with a smaller wavenumber is first created at lower velocities. BEC is destroyed by either of these excitations. The same things can be observed clearly by dragging BEC at constant velocities in ADL. At the moment, we attribute the former and the latter to dynamical instability and energetic instability, respectively.

Free Research Field

数物系科学