Effective two-mode description of a few ultra-cold bosons in a double-well potential

Jacek Dobrzyniecki; Tomasz Sowiński

doi:10.1016/j.physleta.2017.12.027

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arXiv · 1707.04201

Effective two-mode description of a few ultra-cold bosons in a double-well potential

Jacek Dobrzyniecki·Tomasz Sowiński

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Abstract

We present a construction of an improved two-mode model for modeling the dynamics of interacting ultra-cold bosons confined in a one-dimensional double well trap. Unlike in the typically used two-mode model based on the lowest single-particle eigenstates of the external potential, the improved model uses a basis of properly chosen effective wave functions originating in the many-body model. Accuracy of the improved model is examined and it is shown that within a certain limit of inter-particle interaction strength, the model recovers an exact evolution of the wells' populations much more closely than the traditional two-mode model.

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Jacek Dobrzyniecki, Tomasz Sowiński. 2017-12-28. Effective two-mode description of a few ultra-cold bosons in a double-well potential. https://doi.org/10.1016/j.physleta.2017.12.027

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