期刊
ANNALS OF PHYSICS
卷 434, 期 -, 页码 -出版社
ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.aop.2021.168592
关键词
-
资金
- National Research Foundation of Korea [2014R1A2A2A01006535, 2017R1A2A2A05001422, 2020R1A2C2008103]
- Binational USA-Israel Science Foundation [2015616]
- German Aerospace Center (DLR) [50 WM 1957]
- National Research Foundation of Korea [2020R1A2C2008103] Funding Source: Korea Institute of Science & Technology Information (KISTI), National Science & Technology Information Service (NTIS)
The study compares the exact solution and the MCTDH method in a one-dimensional harmonic trap with two interacting bosons, finding that MCTDH accurately reproduces the ground state energy and first order correlations at intermediate coupling strengths. However, for larger couplings, the MCTDH approach tends to overestimate the depth of trap-induced correlation dip and underestimate the fragmentation of orbitals. This suggests that similar features in the correlation function may arise for larger particle numbers, providing a pathway for a quantitative assessment of the accuracy of MCTDH through experiments with ultracold atoms.
We consider two bosons in a one-dimensional harmonic trap, interacting by a contact potential, and compare the exact solution of this problem to a self-consistent numerical solution by using the multiconfigurational time-dependent Hartree (MCTDH) method. We thereby benchmark the predictions of the MCTDH method with a few-body problem that has an analytical solution for the most commonly experimentally realized interaction potential in ultracold quantum gases. It is found that exact ground state energy and first order correlations are accurately reproduced by MCTDH up to the intermediate dimensionless coupling strengths corresponding to typical background scattering lengths of magnetically trapped ultracold dilute Bose gases. For larger couplings, established for example by (a combination of) Feshbach resonances and optical trapping, the MCTDH approach overestimates the depth of the trap-induced correlation dip of first order correlations in position space, and underestimates the fragmentation, defined as the average relative occupation of orbitals other than the energetically lowest one. We anticipate that qualitatively similar features in the correlation function may arise for larger particle numbers, paving the way for a quantitative assessment of the accuracy of MCTDH by experiments with ultracold atoms. (C) 2021 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据