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arXiv · 0802.3818

Dynamical Structure Factor and Spin-Density Separation for a Weakly-Interacting Two-Component Bose Gas

M. -C. Chung·A. B. Bhattacherjee
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Abstract

We show that spin-density separation in a Bose gas is not restricted to 1D but also occurs in higher dimension. The ratio ($α$) of the intra-species atom-atom interaction strength to the inter-species interaction strength, strongly influences the dynamics of spin-density separation and the elementary excitations. The density wave is phonon-like for all values of $α$. For $α<1$, spin wave is also phonon-like. The spin waves have a quadratic dispersion in the $α=1$ coupling regime, while in the phase separated regime ($α>1$) the spin waves are found to be damped. The dynamical structure factor (DSF) reveals two distinct peaks corresponding to the density and spin waves for $α\le 1$. For $α> 1$ there is only one DSF peak corresponding to the density wave.

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M. -C. Chung, A. B. Bhattacherjee. 2008-07-04. Dynamical Structure Factor and Spin-Density Separation for a Weakly-Interacting Two-Component Bose Gas. https://doi.org/10.1103/physrevlett.101.070402

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