Academic Journal

Time-of-flight expansion of binary Bose–Einstein condensates at finite temperature

التفاصيل البيبلوغرافية
العنوان: Time-of-flight expansion of binary Bose–Einstein condensates at finite temperature
المؤلفون: K L Lee, N B Jørgensen, L J Wacker, M G Skou, K T Skalmstang, J J Arlt, N P Proukakis
المصدر: New Journal of Physics, Vol 20, Iss 5, p 053004 (2018)
بيانات النشر: IOP Publishing
سنة النشر: 2018
المجموعة: Directory of Open Access Journals: DOAJ Articles
مصطلحات موضوعية: Bose–Einstein condensation, binary mixture, time-of-flight expansion, miscible–immiscible transition, quantum Boltzmann equation, 03.75.Mn, Science, Physics, QC1-999
الوصف: Ultracold quantum gases provide a unique setting for studying and understanding the properties of interacting quantum systems. Here, we investigate a multi-component system of ^87 Rb– ^39 K Bose–Einstein condensates (BECs) with tunable interactions both theoretically and experimentally. Such multi-component systems can be characterized by their miscibility, where miscible components lead to a mixed ground state and immiscible components form a phase-separated state. Here we perform the first full simulation of the dynamical expansion of this system including both BECs and thermal clouds, which allows for a detailed comparison with experimental results. In particular we show that striking features emerge in time-of-flight (TOF) for BECs with strong interspecies repulsion, even for systems which were separated in situ by a large gravitational sag. An analysis of the centre of mass positions of the BECs after expansion yields qualitative agreement with the homogeneous criterion for phase-separation, but reveals no clear transition point between the mixed and the separated phases. Instead one can identify a transition region, for which the presence of a gravitational sag is found to be advantageous. Moreover, we analyse the situation where only one component is condensed and show that the density distribution of the thermal component also shows some distinct features. Our work sheds new light on the analysis of multi-component systems after TOF and will guide future experiments on the detection of miscibility in these systems.
نوع الوثيقة: article in journal/newspaper
اللغة: English
تدمد: 1367-2630
Relation: https://doi.org/10.1088/1367-2630/aaba39; https://doaj.org/toc/1367-2630; https://doaj.org/article/4a7c5fb7290c49079b57499d8e1b059d
DOI: 10.1088/1367-2630/aaba39
الاتاحة: https://doi.org/10.1088/1367-2630/aaba39
https://doaj.org/article/4a7c5fb7290c49079b57499d8e1b059d
رقم الانضمام: edsbas.A51D9A89
قاعدة البيانات: BASE
الوصف
تدمد:13672630
DOI:10.1088/1367-2630/aaba39