English

Analytical solution for the spectrum of two ultracold atoms in a completely anisotropic confinement

Atomic and Molecular Clusters 2020-05-20 v4 Quantum Gases Atomic Physics Quantum Physics

Abstract

We study the system of two ultracold atoms in a three-dimensional (3D) or two-dimensional (2D) completely anisotropic harmonic trap. We derive the algebraic equation J_{3D}(E) = 1/a_{3D} (J_{2D}(E) = ln a_{2D}) for the eigen-energy E of this system in the 3D (2D) case, with a_{3D} and a_{2D} being the corresponding s-wave scattering lengths, and provide the analytical expressions of the functions J_{3D}(E) and J_{2D}(E). In previous researches this type of equation was obtained for spherically or axially symmetric harmonic traps (T. Busch, et. al., Found. Phys. 28, 549 (1998); Z. Idziaszek and T. Calarco, Phys. Rev. A 74, 022712 (2006)). However, for our cases with a completely anisotropic trap, only the equation for the ground-state energy of some cases has been derived (J. Liang and C. Zhang, Phys. Scr. 77, 025302 (2008)). Our results in this work are applicable for arbitrary eigen-energy of this system, and can be used for the studies of dynamics and thermal-dynamics of interacting ultracold atoms in this trap, e.g., the calculation of the 2nd virial coefficient or the evolution of two-body wave functions. In addition, our approach for the derivation of the above equations can also be used for other two-body problems of ultracold atoms.

Keywords

Cite

@article{arxiv.2002.02168,
  title  = {Analytical solution for the spectrum of two ultracold atoms in a completely anisotropic confinement},
  author = {Yue Chen and Da-Wu Xiao and Ren Zhang and Peng Zhang},
  journal= {arXiv preprint arXiv:2002.02168},
  year   = {2020}
}

Comments

15 pages, 8 figures