低维冷原子体系中基于密度泛函理论严格解的呼吸模研究

基于密度泛函理论(DFT)方法研究了谐振势中自旋双组分费米气体的呼吸模,并同局域密度近似(LDA)的方法相比较.对于排斥相互作用,密度泛函理论给出了更为精确具有Friedel振荡的基态密度分布,其微小振荡使呼吸模略小于LDA的结果;对于弱吸引相互作用,密度泛函给出了更为振荡的密度分布,使呼吸模与LDA的结果有较大的不同,而在强吸引相互作用下,基于Bethe-ansatz解的密度泛函给出了不正确的密度分布,使呼吸模偏离LDA的结果,从而不再准确.

Studies of breathing mode on a one-dimensional cold atomic system based on density functional theory

It was studied the breathing modes on two-component fermi gases under harmonic confinement based on the exact density-functional theory （DFT） , compared against the ones from the local density approxi- mation （LDA }. For a repulsive interaction, DFT gave more accurate ground-state density distribution of Friedel oscillation, which made the breathing mode slightly smaller than the LDA results. However, for the weak attractive interaction, DFT gave more oscillating results, which made the breathing modes from DFT very different from the LDA ones. For the strong attractive interaction, DFT based on the Bethe-ansatz was incor- rect. In this case, the breathing modes deviated from the LDA ones.