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Two component interacting bosons: 1-d exact results

You-Quan Li·Shi-Jian Gu·Zu-Jian Ying·Ulrich Eckern
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Abstract

Motivated by the experiment of two-component Bose-Einstein condensates produced in magnetically trapped $^{87}Rb$, we study one dimensional Boson systems with repulsive $δ$-function interaction in the presence of SU(2) intrinsic degree of freedom by means of coordinate Bethe ansatz. The ground state and low-lying excitations are solved by both numerical and analytical methods. It is shown that the ground state is an isospin-ferromagnetic state and the excitations are composed of three elementary particles: holons, antiholons and isospinons. The isospinon is a triplet coupled to the ``ferromagnetic'' background antiparallelly.

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You-Quan Li, Shi-Jian Gu, Zu-Jian Ying, Ulrich Eckern. 2001-07-27. Two component interacting bosons: 1-d exact results. https://doi.org/10.1209/epl%2Fi2003-00183-2

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