Three and four harmonically trapped particles in an effective-field-theory framework
Three and four harmonically trapped particles in an effective-field-theory framework
复制标题
有效场论框架中的三个和四个谐波捕获粒子
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
U. V. Kolck
中科院分区：
文献类型：
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作者：
J. Rotureau;I. Stetcu;B. Barrett;M. C. Birse;U. V. Kolck
我们研究了在谐振子阱中通过短程相互作用的少数双组分费米子相互作用的系统。优势相互作用是两体相互作用，根据导数的数量进行组织，并在由束缚态基础构成的两体截断模型空间中定义。采用无核壳模型精确求解了前导阶相互作用，而修正则作为多体微扰处理。我们明确地表明，随着模型空间的增加，相邻的lo和相邻的lo相互作用提高了收敛性。我们给出了三费米子和四费米子系统的统一性结果，这些结果与精确解（对于三体问题）和用其他方法得到的结果（在四体情况下）非常一致。我们还给出了有限散射长度和相互作用的非零范围的结果，包括（在正散射长度下）对三体基态结构变化的观察和原子二聚体散射长度的提取。
We study systems of few two-component fermions interacting via short-range interactions within a harmonic-oscillator trap. The dominant interactions, which are two-body interactions, are organized according to the number of derivatives and defined in a two-body truncated model space made from a bound-state basis. Leading-order (LO) interactions are solved for exactly using the formalism of the no-core shell model, whereas corrections are treated as many-body perturbations. We show explicitly that next-to-LO and next-to-next-to-LO interactions improve convergence as the model space increases. We present results at unitarity for three- and four-fermion systems, which show excellent agreement with the exact solution (for the three-body problem) and results obtained by other methods (in the four-body case). We also present results for finite scattering lengths and nonzero range of the interaction, including (at positive scattering length) observation of a change in the structure of the three-body ground state and extraction of the atom-dimer scattering length.